{
 "version": "2.2",
 "instance": {
  "d105453dncsr.htm": {
   "nsprefix": "cik0000832327",
   "nsuri": "http://www.briti/20251231",
   "dts": {
    "schema": {
     "local": [
      "cik0000832327-20251231.xsd"
     ],
     "remote": [
      "http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xl-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xlink-2003-12-31.xsd",
      "http://www.xbrl.org/2005/xbrldt-2005.xsd",
      "http://www.xbrl.org/2006/ref-2006-02-27.xsd",
      "http://www.xbrl.org/2006/xbrldi-2006.xsd",
      "http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd",
      "http://www.xbrl.org/lrr/role/net-2009-12-16.xsd",
      "http://www.xbrl.org/lrr/role/reference-2009-12-16.xsd",
      "https://www.xbrl.org/2020/extensible-enumerations-2.0.xsd",
      "https://www.xbrl.org/dtr/type/2020-01-21/types.xsd",
      "https://www.xbrl.org/dtr/type/2024-01-31/types.xsd",
      "https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd",
      "https://xbrl.fasb.org/srt/2025/elts/srt-roles-2025.xsd",
      "https://xbrl.fasb.org/srt/2025/elts/srt-types-2025.xsd",
      "https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd",
      "https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd",
      "https://xbrl.fasb.org/us-gaap/2025/elts/us-types-2025.xsd",
      "https://xbrl.sec.gov/cef/2025/cef-2025.xsd",
      "https://xbrl.sec.gov/cef/2025/cef-2025_pre.xsd",
      "https://xbrl.sec.gov/country/2025/country-2025.xsd",
      "https://xbrl.sec.gov/dei/2025/dei-2025.xsd",
      "https://xbrl.sec.gov/dei/2025/dei-2025_lab.xsd",
      "https://xbrl.sec.gov/stpr/2025/stpr-2025.xsd"
     ]
    },
    "inline": {
     "local": [
      "d105453dncsr.htm"
     ]
    }
   },
   "keyStandard": 43,
   "keyCustom": 0,
   "axisStandard": 2,
   "axisCustom": 0,
   "memberStandard": 0,
   "memberCustom": 53,
   "hidden": {
    "total": 2,
    "http://xbrl.sec.gov/dei/2025": 2
   },
   "contextCount": 63,
   "entityCount": 1,
   "segmentCount": 53,
   "elementCount": 247,
   "unitCount": 4,
   "baseTaxonomies": {
    "http://xbrl.sec.gov/cef/2025": 131,
    "http://xbrl.sec.gov/dei/2025": 4,
    "http://fasb.org/us-gaap/2025": 2
   },
   "report": {
    "R1": {
     "role": "http://xbrl.sec.gov/cef/role/N2",
     "longName": "995470 - Disclosure - N-2",
     "shortName": "N-2",
     "isDefault": "true",
     "groupType": "disclosure",
     "subGroupType": "",
     "menuCat": "Cover",
     "order": "1",
     "firstAnchor": {
      "contextRef": "P01_01_2025To12_31_2025",
      "name": "dei:DocumentType",
      "unitRef": null,
      "xsiNil": "false",
      "lang": "en-US",
      "decimals": null,
      "ancestors": [
       "div",
       "div",
       "div",
       "div",
       "div",
       "body",
       "html"
      ],
      "reportCount": 1,
      "baseRef": "d105453dncsr.htm",
      "first": true,
      "unique": true
     },
     "uniqueAnchor": {
      "contextRef": "P01_01_2025To12_31_2025",
      "name": "dei:DocumentType",
      "unitRef": null,
      "xsiNil": "false",
      "lang": "en-US",
      "decimals": null,
      "ancestors": [
       "div",
       "div",
       "div",
       "div",
       "div",
       "body",
       "html"
      ],
      "reportCount": 1,
      "baseRef": "d105453dncsr.htm",
      "first": true,
      "unique": true
     }
    }
   },
   "tag": {
    "cef_AcquiredFundFeesAndExpensesNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AcquiredFundFeesAndExpensesNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Acquired Fund Fees and Expenses, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r120"
     ]
    },
    "cef_AcquiredFundFeesAndExpensesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AcquiredFundFeesAndExpensesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Acquired Fund Fees and Expenses [Percent]"
       }
      }
     },
     "auth_ref": [
      "r121"
     ]
    },
    "cef_AcquiredFundFeesEstimatedNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AcquiredFundFeesEstimatedNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Acquired Fund Fees Estimated, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r122"
     ]
    },
    "cef_AcquiredFundIncentiveAllocationNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AcquiredFundIncentiveAllocationNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Acquired Fund Incentive Allocation, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r123"
     ]
    },
    "cef_AcquiredFundTotalAnnualExpensesNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AcquiredFundTotalAnnualExpensesNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Acquired Fund Total Annual Expenses, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r124"
     ]
    },
    "dei_AdditionalSecurities462b": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "AdditionalSecurities462b",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Additional Securities. 462(b)"
       }
      }
     },
     "auth_ref": [
      "r167"
     ]
    },
    "dei_AdditionalSecurities462bFileNumber": {
     "xbrltype": "fileNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "AdditionalSecurities462bFileNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Additional Securities, 462(b), File Number"
       }
      }
     },
     "auth_ref": [
      "r167"
     ]
    },
    "dei_AdditionalSecuritiesEffective413b": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "AdditionalSecuritiesEffective413b",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Additional Securities Effective, 413(b)"
       }
      }
     },
     "auth_ref": [
      "r166"
     ]
    },
    "dei_AddressTypeDomain": {
     "xbrltype": "domainItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "AddressTypeDomain",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Address Type [Domain]",
        "documentation": "An entity may have several addresses for different purposes and this domain represents all such types."
       }
      }
     },
     "auth_ref": []
    },
    "cef_AllCoregistrantsMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AllCoregistrantsMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "All Coregistrants [Member]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cef_AllRisksMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AllRisksMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "All Risks:"
       }
      }
     },
     "auth_ref": [
      "r146"
     ]
    },
    "dei_AmendmentDescription": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "AmendmentDescription",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Amendment Description",
        "documentation": "Description of changes contained within amended document."
       }
      }
     },
     "auth_ref": []
    },
    "dei_AmendmentFlag": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "AmendmentFlag",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Amendment Flag",
        "documentation": "Boolean flag that is true when the XBRL content amends previously-filed or accepted submission."
       }
      }
     },
     "auth_ref": []
    },
    "cef_AnnualCoverageReturnRatePercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AnnualCoverageReturnRatePercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Annual Coverage Return Rate [Percent]"
       }
      }
     },
     "auth_ref": [
      "r149"
     ]
    },
    "cef_AnnualDividendPayment": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AnnualDividendPayment",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Annual Dividend Payment"
       }
      }
     },
     "auth_ref": [
      "r148"
     ]
    },
    "cef_AnnualDividendPaymentCurrent": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AnnualDividendPaymentCurrent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Annual Dividend Payment, Current"
       }
      }
     },
     "auth_ref": [
      "r148"
     ]
    },
    "cef_AnnualDividendPaymentInitial": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AnnualDividendPaymentInitial",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Annual Dividend Payment, Initial"
       }
      }
     },
     "auth_ref": [
      "r148"
     ]
    },
    "cef_AnnualExpensesTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AnnualExpensesTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Annual Expenses [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r128"
     ]
    },
    "cef_AnnualInterestRateCurrentPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AnnualInterestRateCurrentPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Annual Interest Rate, Current [Percent]"
       }
      }
     },
     "auth_ref": [
      "r148"
     ]
    },
    "cef_AnnualInterestRateInitialPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AnnualInterestRateInitialPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Annual Interest Rate, Initial [Percent]"
       }
      }
     },
     "auth_ref": [
      "r148"
     ]
    },
    "cef_AnnualInterestRatePercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "AnnualInterestRatePercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Annual Interest Rate [Percent]"
       }
      }
     },
     "auth_ref": [
      "r148"
     ]
    },
    "dei_ApproximateDateOfCommencementOfProposedSaleToThePublic": {
     "xbrltype": "dateOrAsapItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "ApproximateDateOfCommencementOfProposedSaleToThePublic",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Approximate Date of Commencement of Proposed Sale to Public",
        "documentation": "The approximate date of a commencement of a proposed sale of securities to the public. This element is disclosed in S-1, S-3, S-4, S-11, F-1, F-3 and F-10 filings."
       }
      }
     },
     "auth_ref": []
    },
    "cef_BasisOfTransactionFeesNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "BasisOfTransactionFeesNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Basis of Transaction Fees, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r126"
     ]
    },
    "cef_BdcFileNumber": {
     "xbrltype": "fileNumberItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "BdcFileNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "BDC File Number"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_BradyBondsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "BradyBondsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Brady Bonds Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "dei_BusinessContactMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "BusinessContactMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Business Contact [Member]",
        "documentation": "Business contact for the entity"
       }
      }
     },
     "auth_ref": [
      "r90",
      "r91"
     ]
    },
    "cef_BusinessDevelopmentCompanyFlag": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "BusinessDevelopmentCompanyFlag",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Business Development Company [Flag]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cik0000832327_CLORiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "CLORiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "CLO Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_CapitalStockLongTermDebtAndOtherSecuritiesAbstract": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "CapitalStockLongTermDebtAndOtherSecuritiesAbstract",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Capital Stock, Long-Term Debt, and Other Securities [Abstract]"
       }
      }
     },
     "auth_ref": [
      "r94"
     ]
    },
    "cef_CapitalStockTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "CapitalStockTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Capital Stock [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r95"
     ]
    },
    "dei_CityAreaCode": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "CityAreaCode",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "City Area Code",
        "documentation": "Area code of city"
       }
      }
     },
     "auth_ref": []
    },
    "us-gaap_ClassOfStockDomain": {
     "xbrltype": "domainItemType",
     "nsuri": "http://fasb.org/us-gaap/2025",
     "localname": "ClassOfStockDomain",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Share of stock differentiated by the voting rights the holder receives. Examples include, but are not limited to, common stock, redeemable preferred stock, nonredeemable preferred stock, and convertible stock."
       }
      }
     },
     "auth_ref": [
      "r8",
      "r9",
      "r10",
      "r11",
      "r12",
      "r13",
      "r14",
      "r15",
      "r16",
      "r17",
      "r18",
      "r19",
      "r20",
      "r21",
      "r22",
      "r23",
      "r24",
      "r25",
      "r26",
      "r43",
      "r44",
      "r45",
      "r46",
      "r47",
      "r48",
      "r49",
      "r50",
      "r51",
      "r52",
      "r53",
      "r54",
      "r55",
      "r56",
      "r57",
      "r58",
      "r59",
      "r60",
      "r61",
      "r62",
      "r63",
      "r64",
      "r65",
      "r66",
      "r67",
      "r68",
      "r69",
      "r70",
      "r71",
      "r74",
      "r75",
      "r76",
      "r77",
      "r78",
      "r79",
      "r80",
      "r175",
      "r178",
      "r180",
      "r182"
     ]
    },
    "cik0000832327_CollateralizedBondObligationsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "CollateralizedBondObligationsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Collateralized Bond Obligations Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_CollateralizedDebtObligationsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "CollateralizedDebtObligationsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Collateralized Debt Obligations Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_CommonSharesMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "CommonSharesMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Common Shares [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_ConcentrationRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "ConcentrationRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Concentration Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "dei_ContactPersonnelName": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "ContactPersonnelName",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Contact Personnel Name",
        "documentation": "Name of contact personnel"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_ConvertibleSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "ConvertibleSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Convertible Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_CoregistrantAxis": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "CoregistrantAxis",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Coregistrant [Axis]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cik0000832327_CorporateLoansRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "CorporateLoansRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Corporate Loans Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_CounterpartyCreditRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "CounterpartyCreditRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Counterparty Credit Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "dei_CoverAbstract": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "CoverAbstract",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Cover [Abstract]",
        "documentation": "Cover page."
       }
      }
     },
     "auth_ref": []
    },
    "us-gaap_DebtInstrumentAxis": {
     "xbrltype": "stringItemType",
     "nsuri": "http://fasb.org/us-gaap/2025",
     "localname": "DebtInstrumentAxis",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Debt Instrument [Axis]",
        "documentation": "Information by type of debt instrument, including, but not limited to, draws against credit facilities."
       }
      }
     },
     "auth_ref": [
      "r0",
      "r3",
      "r4",
      "r6",
      "r7",
      "r27",
      "r28",
      "r29",
      "r30",
      "r31",
      "r32",
      "r33",
      "r34",
      "r35",
      "r36",
      "r37",
      "r38",
      "r39",
      "r40",
      "r41",
      "r42",
      "r81",
      "r82",
      "r83",
      "r84",
      "r85",
      "r86",
      "r176",
      "r177",
      "r179",
      "r181",
      "r183",
      "r184",
      "r185",
      "r187",
      "r188",
      "r189"
     ]
    },
    "us-gaap_DebtInstrumentNameDomain": {
     "xbrltype": "domainItemType",
     "nsuri": "http://fasb.org/us-gaap/2025",
     "localname": "DebtInstrumentNameDomain",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The name for the particular debt instrument or borrowing that distinguishes it from other debt instruments or borrowings, including draws against credit facilities."
       }
      }
     },
     "auth_ref": [
      "r0",
      "r27",
      "r28",
      "r29",
      "r30",
      "r31",
      "r32",
      "r33",
      "r34",
      "r35",
      "r36",
      "r37",
      "r38",
      "r39",
      "r40",
      "r41",
      "r42",
      "r81",
      "r82",
      "r83",
      "r84",
      "r85",
      "r86",
      "r176",
      "r177",
      "r179",
      "r181",
      "r183",
      "r184",
      "r185",
      "r187",
      "r188",
      "r189"
     ]
    },
    "cik0000832327_DebtSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "DebtSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Debt Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "dei_DelayedOrContinuousOffering": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "DelayedOrContinuousOffering",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Delayed or Continuous Offering"
       }
      }
     },
     "auth_ref": [
      "r92",
      "r93",
      "r162"
     ]
    },
    "cik0000832327_DerivativesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "DerivativesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Derivatives Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_DistressedSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "DistressedSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Distressed Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_DistributionServicingFeesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "DistributionServicingFeesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Distribution/Servicing Fees [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_DistributionsMayReducePrincipalTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "DistributionsMayReducePrincipalTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Distributions May Reduce Principal [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r102"
     ]
    },
    "cef_DividendAndInterestExpensesOnShortSalesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "DividendAndInterestExpensesOnShortSalesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Dividend and Interest Expenses on Short Sales [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_DividendExpenseOnPreferredSharesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "DividendExpenseOnPreferredSharesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Dividend Expenses on Preferred Shares [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "dei_DividendOrInterestReinvestmentPlanOnly": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "DividendOrInterestReinvestmentPlanOnly",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Dividend or Interest Reinvestment Plan Only"
       }
      }
     },
     "auth_ref": [
      "r92",
      "r93",
      "r162"
     ]
    },
    "cef_DividendReinvestmentAndCashPurchaseFees": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "DividendReinvestmentAndCashPurchaseFees",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Dividend Reinvestment and Cash Purchase Fees"
       }
      }
     },
     "auth_ref": [
      "r118"
     ]
    },
    "dei_DocumentRegistrationStatement": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "DocumentRegistrationStatement",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Document Registration Statement",
        "documentation": "Boolean flag that is true only for a form used as a registration statement."
       }
      }
     },
     "auth_ref": [
      "r88"
     ]
    },
    "dei_DocumentType": {
     "xbrltype": "submissionTypeItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "DocumentType",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Document Type",
        "documentation": "The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'."
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_DollarRollsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "DollarRollsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Dollar Rolls Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EffectiveAfter60Days486a": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EffectiveAfter60Days486a",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effective after 60 Days, 486(a)"
       }
      }
     },
     "auth_ref": [
      "r171"
     ]
    },
    "dei_EffectiveOnDate486a": {
     "xbrltype": "dateItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EffectiveOnDate486a",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effective on Date, 486(a)"
       }
      }
     },
     "auth_ref": [
      "r171"
     ]
    },
    "dei_EffectiveOnDate486b": {
     "xbrltype": "dateItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EffectiveOnDate486b",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effective on Date, 486(b)"
       }
      }
     },
     "auth_ref": [
      "r172"
     ]
    },
    "dei_EffectiveOnSetDate486a": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EffectiveOnSetDate486a",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effective on Set Date, 486(a)"
       }
      }
     },
     "auth_ref": [
      "r171"
     ]
    },
    "dei_EffectiveOnSetDate486b": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EffectiveOnSetDate486b",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effective on Set Date, 486(b)"
       }
      }
     },
     "auth_ref": [
      "r172"
     ]
    },
    "dei_EffectiveUponFiling462e": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EffectiveUponFiling462e",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effective Upon Filing, 462(e)"
       }
      }
     },
     "auth_ref": [
      "r170"
     ]
    },
    "dei_EffectiveUponFiling486b": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EffectiveUponFiling486b",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effective upon Filing, 486(b)"
       }
      }
     },
     "auth_ref": [
      "r172"
     ]
    },
    "dei_EffectiveWhenDeclaredSection8c": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EffectiveWhenDeclaredSection8c",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effective when Declared, Section 8(c)"
       }
      }
     },
     "auth_ref": [
      "r174"
     ]
    },
    "cef_EffectsOfLeveragePurposeTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "EffectsOfLeveragePurposeTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effects of Leverage, Purpose [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r150"
     ]
    },
    "cef_EffectsOfLeverageTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "EffectsOfLeverageTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effects of Leverage [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r150"
     ]
    },
    "cef_EffectsOfLeverageTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "EffectsOfLeverageTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Effects of Leverage [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r147"
     ]
    },
    "cik0000832327_EmergingMarketsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "EmergingMarketsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Emerging Markets Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressAddressLine1": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityAddressAddressLine1",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, Address Line One",
        "documentation": "Address Line 1 such as Attn, Building Name, Street Name"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressAddressLine2": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityAddressAddressLine2",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, Address Line Two",
        "documentation": "Address Line 2 such as Street or Suite number"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressAddressLine3": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityAddressAddressLine3",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, Address Line Three",
        "documentation": "Address Line 3 such as an Office Park"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressCityOrTown": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityAddressCityOrTown",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, City or Town",
        "documentation": "Name of the City or Town"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressPostalZipCode": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityAddressPostalZipCode",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, Postal Zip Code",
        "documentation": "Code for the postal or zip code"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressStateOrProvince": {
     "xbrltype": "stateOrProvinceItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityAddressStateOrProvince",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, State or Province",
        "documentation": "Name of the state or province."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressesAddressTypeAxis": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityAddressesAddressTypeAxis",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Addresses, Address Type [Axis]",
        "documentation": "The axis of a table defines the relationship between the domain members or categories in the table and the line items or concepts that complete the table."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityCentralIndexKey": {
     "xbrltype": "centralIndexKeyItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityCentralIndexKey",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Central Index Key",
        "documentation": "A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK."
       }
      }
     },
     "auth_ref": [
      "r89"
     ]
    },
    "dei_EntityEmergingGrowthCompany": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityEmergingGrowthCompany",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Emerging Growth Company",
        "documentation": "Indicate if registrant meets the emerging growth company criteria."
       }
      }
     },
     "auth_ref": [
      "r89"
     ]
    },
    "dei_EntityExTransitionPeriod": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityExTransitionPeriod",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Ex Transition Period",
        "documentation": "Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards."
       }
      }
     },
     "auth_ref": [
      "r173"
     ]
    },
    "dei_EntityFileNumber": {
     "xbrltype": "fileNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityFileNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Securities Act File Number",
        "documentation": "Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityInvCompanyType": {
     "xbrltype": "invCompanyType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityInvCompanyType",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Inv Company Type",
        "documentation": "One of: N-1A (Mutual Fund), N-1 (Open-End Separate Account with No Variable Annuities), N-2 (Closed-End Investment Company), N-3 (Separate Account Registered as Open-End Management Investment Company), N-4 (Variable Annuity UIT Separate Account), N-5 (Small Business Investment Company), N-6 (Variable Life UIT Separate Account), S-1 or S-3 (Face Amount Certificate Company), S-6 (UIT, Non-Insurance Product)."
       }
      }
     },
     "auth_ref": [
      "r164"
     ]
    },
    "dei_EntityRegistrantName": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityRegistrantName",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Registrant Name",
        "documentation": "The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC."
       }
      }
     },
     "auth_ref": [
      "r89"
     ]
    },
    "dei_EntityWellKnownSeasonedIssuer": {
     "xbrltype": "yesNoItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "EntityWellKnownSeasonedIssuer",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Well-known Seasoned Issuer",
        "documentation": "Indicate 'Yes' or 'No' if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Is used on Form Type: 10-K, 10-Q, 8-K, 20-F, 6-K, 10-K/A, 10-Q/A, 20-F/A, 6-K/A, N-CSR, N-Q, N-1A."
       }
      }
     },
     "auth_ref": [
      "r165"
     ]
    },
    "cik0000832327_EquitySecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "EquitySecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Equity Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "dei_ExhibitsOnly462d": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "ExhibitsOnly462d",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Exhibits Only, 462(d)"
       }
      }
     },
     "auth_ref": [
      "r169"
     ]
    },
    "dei_ExhibitsOnly462dFileNumber": {
     "xbrltype": "fileNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "ExhibitsOnly462dFileNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Exhibits Only, 462(d), File Number"
       }
      }
     },
     "auth_ref": [
      "r169"
     ]
    },
    "cef_ExpenseExampleTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ExpenseExampleTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Expense Example [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r118"
     ]
    },
    "cef_ExpenseExampleYear01": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ExpenseExampleYear01",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Expense Example, Year 01"
       }
      }
     },
     "auth_ref": [
      "r125"
     ]
    },
    "cef_ExpenseExampleYears1to10": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ExpenseExampleYears1to10",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Expense Example, Years 1 to 10"
       }
      }
     },
     "auth_ref": [
      "r125"
     ]
    },
    "cef_ExpenseExampleYears1to3": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ExpenseExampleYears1to3",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Expense Example, Years 1 to 3"
       }
      }
     },
     "auth_ref": [
      "r125"
     ]
    },
    "cef_ExpenseExampleYears1to5": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ExpenseExampleYears1to5",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Expense Example, Years 1 to 5"
       }
      }
     },
     "auth_ref": [
      "r125"
     ]
    },
    "cef_FeeTableAbstract": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "FeeTableAbstract",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Fee Table [Abstract]"
       }
      }
     },
     "auth_ref": [
      "r118"
     ]
    },
    "cef_FinancialHighlightsAbstract": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "FinancialHighlightsAbstract",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Financial Highlights [Abstract]"
       }
      }
     },
     "auth_ref": [
      "r133"
     ]
    },
    "cik0000832327_ForeignSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "ForeignSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Foreign Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_GeneralDescriptionOfRegistrantAbstract": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "GeneralDescriptionOfRegistrantAbstract",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "General Description of Registrant [Abstract]"
       }
      }
     },
     "auth_ref": [
      "r144"
     ]
    },
    "cik0000832327_GeographicAssetClassRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "GeographicAssetClassRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Geographic/Asset Class Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_HighYieldBondsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "HighYieldBondsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "High Yield Bonds Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_HighestPriceOrBid": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "HighestPriceOrBid",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Highest Price or Bid"
       }
      }
     },
     "auth_ref": [
      "r151"
     ]
    },
    "cef_HighestPriceOrBidNav": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "HighestPriceOrBidNav",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Highest Price or Bid, NAV"
       }
      }
     },
     "auth_ref": [
      "r155"
     ]
    },
    "cef_HighestPriceOrBidPremiumDiscountToNavPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "HighestPriceOrBidPremiumDiscountToNavPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Highest Price or Bid, Premium (Discount) to NAV [Percent]"
       }
      }
     },
     "auth_ref": [
      "r156"
     ]
    },
    "cik0000832327_IlliquidInvestmentsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "IlliquidInvestmentsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Illiquid Investments Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_IlliquidityRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "IlliquidityRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Illiquidity Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_IncentiveAllocationMaximumPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "IncentiveAllocationMaximumPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Incentive Allocation Maximum [Percent]"
       }
      }
     },
     "auth_ref": [
      "r123"
     ]
    },
    "cef_IncentiveAllocationMinimumPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "IncentiveAllocationMinimumPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Incentive Allocation Minimum [Percent]"
       }
      }
     },
     "auth_ref": [
      "r123"
     ]
    },
    "cef_IncentiveAllocationPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "IncentiveAllocationPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Incentive Allocation [Percent]"
       }
      }
     },
     "auth_ref": [
      "r123"
     ]
    },
    "cef_IncentiveFeesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "IncentiveFeesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Incentive Fees [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_InterestExpensesOnBorrowingsPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "InterestExpensesOnBorrowingsPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Interest Expenses on Borrowings [Percent]"
       }
      }
     },
     "auth_ref": [
      "r131"
     ]
    },
    "us-gaap_InterestRateRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://fasb.org/us-gaap/2025",
     "localname": "InterestRateRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Interest Rate Risk [Member]",
        "documentation": "The risk associated with changes in interest rates that effect the value of an interest-bearing asset or liability, and a servicing asset or liability."
       }
      }
     },
     "auth_ref": []
    },
    "cef_IntervalFundFlag": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "IntervalFundFlag",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Interval Fund [Flag]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cik0000832327_InverseFloaterandRelatedSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "InverseFloaterandRelatedSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Inverse Floater and Related Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_InvestmentCompaniesandETFsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "InvestmentCompaniesandETFsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment Companies and ETFs Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "dei_InvestmentCompanyActFileNumber": {
     "xbrltype": "fileNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "InvestmentCompanyActFileNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment Company Act File Number"
       }
      }
     },
     "auth_ref": [
      "r93",
      "r159",
      "r160",
      "r161"
     ]
    },
    "dei_InvestmentCompanyActRegistration": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "InvestmentCompanyActRegistration",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment Company Act Registration"
       }
      }
     },
     "auth_ref": [
      "r163"
     ]
    },
    "dei_InvestmentCompanyRegistrationAmendment": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "InvestmentCompanyRegistrationAmendment",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment Company Registration Amendment"
       }
      }
     },
     "auth_ref": [
      "r163"
     ]
    },
    "dei_InvestmentCompanyRegistrationAmendmentNumber": {
     "xbrltype": "sequenceNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "InvestmentCompanyRegistrationAmendmentNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment Company Registration Amendment Number"
       }
      }
     },
     "auth_ref": [
      "r163"
     ]
    },
    "cik0000832327_InvestmentObjectiveMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "InvestmentObjectiveMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment Objective [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_InvestmentObjectivesAndPoliciesMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "InvestmentObjectivesAndPoliciesMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment Objectives And Policies [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_InvestmentObjectivesAndPracticesTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "InvestmentObjectivesAndPracticesTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment Objectives and Practices [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r145"
     ]
    },
    "cik0000832327_InvestmentandMarketDiscountRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "InvestmentandMarketDiscountRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Investment and Market Discount Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_LatestPremiumDiscountToNavPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LatestPremiumDiscountToNavPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Latest Premium (Discount) to NAV [Percent]"
       }
      }
     },
     "auth_ref": [
      "r157"
     ]
    },
    "cik0000832327_LeverageRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "LeverageRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Leverage Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_LoanServicingFeesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LoanServicingFeesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Loan Servicing Fees [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "dei_LocalPhoneNumber": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "LocalPhoneNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Local Phone Number",
        "documentation": "Local phone number for entity."
       }
      }
     },
     "auth_ref": []
    },
    "cef_LongTermDebtDividendsAndCovenantsTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LongTermDebtDividendsAndCovenantsTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Long Term Debt, Dividends and Covenants [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r109"
     ]
    },
    "cef_LongTermDebtIssuanceAndSubstitutionTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LongTermDebtIssuanceAndSubstitutionTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Long Term Debt, Issuance and Substitution [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r110"
     ]
    },
    "cef_LongTermDebtPrincipal": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LongTermDebtPrincipal",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Long Term Debt, Principal"
       }
      }
     },
     "auth_ref": [
      "r107"
     ]
    },
    "cef_LongTermDebtRightsLimitedByOtherSecuritiesTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LongTermDebtRightsLimitedByOtherSecuritiesTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Long Term Debt, Rights Limited by Other Securities [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r111"
     ]
    },
    "cef_LongTermDebtStructuringTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LongTermDebtStructuringTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Long Term Debt, Structuring [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r108"
     ]
    },
    "cef_LongTermDebtTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LongTermDebtTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Long Term Debt [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r107"
     ]
    },
    "cef_LongTermDebtTitleTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LongTermDebtTitleTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Long Term Debt, Title [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r107"
     ]
    },
    "cef_LowestPriceOrBid": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LowestPriceOrBid",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Lowest Price or Bid"
       }
      }
     },
     "auth_ref": [
      "r151"
     ]
    },
    "cef_LowestPriceOrBidNav": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LowestPriceOrBidNav",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Lowest Price or Bid, NAV"
       }
      }
     },
     "auth_ref": [
      "r155"
     ]
    },
    "cef_LowestPriceOrBidPremiumDiscountToNavPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "LowestPriceOrBidPremiumDiscountToNavPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Lowest Price or Bid, Premium (Discount) to NAV [Percent]"
       }
      }
     },
     "auth_ref": [
      "r156"
     ]
    },
    "cef_ManagementFeeNotBasedOnNetAssetsNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ManagementFeeNotBasedOnNetAssetsNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Management Fee not based on Net Assets, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r130"
     ]
    },
    "cef_ManagementFeesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ManagementFeesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Management Fees [Percent]"
       }
      }
     },
     "auth_ref": [
      "r129"
     ]
    },
    "cik0000832327_MarketRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "MarketRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Market Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_MarketRiskandSelectionRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "MarketRiskandSelectionRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Market Risk and Selection Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_MortgageandAssetBackedSecuritiesRisksMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "MortgageandAssetBackedSecuritiesRisksMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Mortgage- and Asset-Backed Securities Risks [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_MunicipalSecuritiesRisksMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "MunicipalSecuritiesRisksMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Municipal Securities Risks [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "us-gaap_NetAssetValuePerShare": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://fasb.org/us-gaap/2025",
     "localname": "NetAssetValuePerShare",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "NAV Per Share",
        "documentation": "Net asset value per share or per unit of investments in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes fair value disclosure."
       }
      }
     },
     "auth_ref": [
      "r62",
      "r69",
      "r70",
      "r72",
      "r73",
      "r76",
      "r87"
     ]
    },
    "cef_NetExpenseOverAssetsPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "NetExpenseOverAssetsPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Net Expense over Assets [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_NewCefOrBdcRegistrantFlag": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "NewCefOrBdcRegistrantFlag",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "New CEF or BDC Registrant [Flag]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "dei_NewEffectiveDateForPreviousFiling": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "NewEffectiveDateForPreviousFiling",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "New Effective Date for Previous Filing"
       }
      }
     },
     "auth_ref": [
      "r93",
      "r159",
      "r160",
      "r161"
     ]
    },
    "cef_NoPublicTradingTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "NoPublicTradingTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "No Public Trading [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r154"
     ]
    },
    "dei_NoSubstantiveChanges462c": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "NoSubstantiveChanges462c",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "No Substantive Changes, 462(c)"
       }
      }
     },
     "auth_ref": [
      "r168"
     ]
    },
    "dei_NoSubstantiveChanges462cFileNumber": {
     "xbrltype": "fileNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "NoSubstantiveChanges462cFileNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "No Substantive Changes, 462(c), File Number"
       }
      }
     },
     "auth_ref": [
      "r168"
     ]
    },
    "cef_NoTradingHistoryTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "NoTradingHistoryTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "No Trading History [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r158"
     ]
    },
    "cef_OtherAnnualExpense1Percent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherAnnualExpense1Percent",
     "calculation": {
      "http://xbrl.sec.gov/cef/role/Item3Ae": {
       "parentTag": "cef_OtherAnnualExpensesPercent",
       "weight": 1.0,
       "order": 1.0
      }
     },
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Annual Expense 1 [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_OtherAnnualExpense2Percent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherAnnualExpense2Percent",
     "calculation": {
      "http://xbrl.sec.gov/cef/role/Item3Ae": {
       "parentTag": "cef_OtherAnnualExpensesPercent",
       "weight": 1.0,
       "order": 2.0
      }
     },
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Annual Expense 2 [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_OtherAnnualExpense3Percent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherAnnualExpense3Percent",
     "calculation": {
      "http://xbrl.sec.gov/cef/role/Item3Ae": {
       "parentTag": "cef_OtherAnnualExpensesPercent",
       "weight": 1.0,
       "order": 3.0
      }
     },
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Annual Expense 3 [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_OtherAnnualExpensesAbstract": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherAnnualExpensesAbstract",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Annual Expenses [Abstract]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_OtherAnnualExpensesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherAnnualExpensesPercent",
     "calculation": {
      "http://xbrl.sec.gov/cef/role/Item3Ae": {
       "parentTag": null,
       "weight": null,
       "order": null,
       "root": true
      }
     },
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Annual Expenses [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_OtherExpensesNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherExpensesNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Expenses, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r128"
     ]
    },
    "cef_OtherFeederFundExpensesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherFeederFundExpensesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Feeder Fund Expenses [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_OtherMasterFundExpensesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherMasterFundExpensesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Master Fund Expenses [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_OtherSecuritiesTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherSecuritiesTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Securities [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r112"
     ]
    },
    "cef_OtherSecurityDescriptionTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherSecurityDescriptionTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Security, Description [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r112"
     ]
    },
    "cef_OtherSecurityTitleTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherSecurityTitleTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Security, Title [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r112"
     ]
    },
    "cef_OtherTransactionExpense1Percent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionExpense1Percent",
     "calculation": {
      "http://xbrl.sec.gov/cef/role/Item3Te": {
       "parentTag": "cef_OtherTransactionExpensesPercent",
       "weight": 1.0,
       "order": 1.0
      }
     },
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Expense 1 [Percent]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OtherTransactionExpense2Percent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionExpense2Percent",
     "calculation": {
      "http://xbrl.sec.gov/cef/role/Item3Te": {
       "parentTag": "cef_OtherTransactionExpensesPercent",
       "weight": 1.0,
       "order": 2.0
      }
     },
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Expense 2 [Percent]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OtherTransactionExpense3Percent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionExpense3Percent",
     "calculation": {
      "http://xbrl.sec.gov/cef/role/Item3Te": {
       "parentTag": "cef_OtherTransactionExpensesPercent",
       "weight": 1.0,
       "order": 3.0
      }
     },
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Expense 3 [Percent]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OtherTransactionExpensesAbstract": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionExpensesAbstract",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Expenses [Abstract]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OtherTransactionExpensesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionExpensesPercent",
     "calculation": {
      "http://xbrl.sec.gov/cef/role/Item3Te": {
       "parentTag": null,
       "weight": null,
       "order": null,
       "root": true
      }
     },
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Expenses [Percent]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OtherTransactionFeesBasisMaximum": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionFeesBasisMaximum",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Fees Basis, Maximum"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OtherTransactionFeesBasisMaximumPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionFeesBasisMaximumPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Fees Basis, Maximum [Percent]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OtherTransactionFeesBasisNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionFeesBasisNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Fees Basis, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OtherTransactionFeesNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OtherTransactionFeesNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Transaction Fees, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cef_OutstandingSecuritiesTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OutstandingSecuritiesTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Outstanding Securities [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r113"
     ]
    },
    "cef_OutstandingSecurityAuthorizedShares": {
     "xbrltype": "sharesItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OutstandingSecurityAuthorizedShares",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Outstanding Security, Authorized [Shares]"
       }
      }
     },
     "auth_ref": [
      "r115"
     ]
    },
    "cef_OutstandingSecurityHeldShares": {
     "xbrltype": "sharesItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OutstandingSecurityHeldShares",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Outstanding Security, Held [Shares]"
       }
      }
     },
     "auth_ref": [
      "r116"
     ]
    },
    "cef_OutstandingSecurityNotHeldShares": {
     "xbrltype": "sharesItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OutstandingSecurityNotHeldShares",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Outstanding Security, Not Held [Shares]"
       }
      }
     },
     "auth_ref": [
      "r117"
     ]
    },
    "cef_OutstandingSecurityTitleTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "OutstandingSecurityTitleTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Outstanding Security, Title [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r114"
     ]
    },
    "dei_PostEffectiveAmendment": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "PostEffectiveAmendment",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Post-Effective Amendment"
       }
      }
     },
     "auth_ref": [
      "r88"
     ]
    },
    "dei_PostEffectiveAmendmentNumber": {
     "xbrltype": "sequenceNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "PostEffectiveAmendmentNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Post-Effective Amendment Number",
        "documentation": "Amendment number to registration statement under the Securities Act of 1933 after the registration becomes effective."
       }
      }
     },
     "auth_ref": [
      "r88"
     ]
    },
    "dei_PreEffectiveAmendment": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "PreEffectiveAmendment",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Pre-Effective Amendment"
       }
      }
     },
     "auth_ref": [
      "r88"
     ]
    },
    "dei_PreEffectiveAmendmentNumber": {
     "xbrltype": "sequenceNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2025",
     "localname": "PreEffectiveAmendmentNumber",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Pre-Effective Amendment Number",
        "documentation": "Amendment number to registration statement under the Securities Act of 1933 before the registration becomes effective."
       }
      }
     },
     "auth_ref": [
      "r88"
     ]
    },
    "cik0000832327_PreferredSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "PreferredSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Preferred Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "us-gaap_PreferredStockLiquidationPreference": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://fasb.org/us-gaap/2025",
     "localname": "PreferredStockLiquidationPreference",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Preferred Stock Liquidating Preference",
        "documentation": "The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share."
       }
      }
     },
     "auth_ref": [
      "r1",
      "r2",
      "r5",
      "r176",
      "r178",
      "r186"
     ]
    },
    "cef_PreferredStockRestrictionsArrearageTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "PreferredStockRestrictionsArrearageTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Preferred Stock Restrictions, Arrearage [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r103"
     ]
    },
    "cef_PreferredStockRestrictionsOtherTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "PreferredStockRestrictionsOtherTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Preferred Stock Restrictions, Other [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r104"
     ]
    },
    "cef_PrimaryShelfFlag": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "PrimaryShelfFlag",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Primary Shelf [Flag]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cef_PrimaryShelfQualifiedFlag": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "PrimaryShelfQualifiedFlag",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Primary Shelf Qualified [Flag]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cef_ProspectusLineItems": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ProspectusLineItems",
     "lang": {
      "en-us": {
       "role": {
        "label": "Prospectus [Line Items]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cef_ProspectusTable": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ProspectusTable",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Prospectus:"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cef_PurposeOfFeeTableNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "PurposeOfFeeTableNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Purpose of Fee Table , Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r119"
     ]
    },
    "cik0000832327_REITInvestmentRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "REITInvestmentRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "REIT Investment Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_RealEstateRelatedSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "RealEstateRelatedSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Real Estate-Related Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_RegisteredClosedEndFundFlag": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "RegisteredClosedEndFundFlag",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Registered Closed-End Fund [Flag]"
       }
      }
     },
     "auth_ref": [
      "r93"
     ]
    },
    "cik0000832327_RepurchaseAgreementsandPurchaseandSaleContractsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "RepurchaseAgreementsandPurchaseandSaleContractsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Repurchase Agreements and Purchase and Sale Contracts Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_ReturnAtMinusFivePercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ReturnAtMinusFivePercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Return at Minus Five [Percent]"
       }
      }
     },
     "auth_ref": [
      "r150"
     ]
    },
    "cef_ReturnAtMinusTenPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ReturnAtMinusTenPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Return at Minus Ten [Percent]"
       }
      }
     },
     "auth_ref": [
      "r150"
     ]
    },
    "cef_ReturnAtPlusFivePercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ReturnAtPlusFivePercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Return at Plus Five [Percent]"
       }
      }
     },
     "auth_ref": [
      "r150"
     ]
    },
    "cef_ReturnAtPlusTenPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ReturnAtPlusTenPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Return at Plus Ten [Percent]"
       }
      }
     },
     "auth_ref": [
      "r150"
     ]
    },
    "cef_ReturnAtZeroPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ReturnAtZeroPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Return at Zero [Percent]"
       }
      }
     },
     "auth_ref": [
      "r150"
     ]
    },
    "cik0000832327_ReverseRepurchaseAgreementsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "ReverseRepurchaseAgreementsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Reverse Repurchase Agreements Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_RightsLimitedByOtherSecuritiesTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "RightsLimitedByOtherSecuritiesTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Rights Limited by Other Securities [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r106"
     ]
    },
    "cef_RightsSubjectToOtherThanMajorityVoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "RightsSubjectToOtherThanMajorityVoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Rights Subject to Other than Majority Vote [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r105"
     ]
    },
    "cef_RiskAxis": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "RiskAxis",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Risk [Axis]"
       }
      }
     },
     "auth_ref": [
      "r146"
     ]
    },
    "cef_RiskFactorsTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "RiskFactorsTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Risk Factors [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r146"
     ]
    },
    "cef_RiskTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "RiskTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Risk [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r146"
     ]
    },
    "cik0000832327_RiskofInvestingintheUnitedStatesMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "RiskofInvestingintheUnitedStatesMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Risk of Investing in the United States [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_RisksofLoanAssignmentsandParticipationsMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "RisksofLoanAssignmentsandParticipationsMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Risks of Loan Assignments and Participations [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_SalesLoadPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SalesLoadPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Sales Load [Percent]"
       }
      }
     },
     "auth_ref": [
      "r118"
     ]
    },
    "cik0000832327_SecondLienLoansRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "SecondLienLoansRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Second Lien Loans Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_SecurityDividendsTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SecurityDividendsTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Security Dividends [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r96"
     ]
    },
    "cef_SecurityLiabilitiesTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SecurityLiabilitiesTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Security Liabilities [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r99"
     ]
    },
    "cef_SecurityLiquidationRightsTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SecurityLiquidationRightsTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Security Liquidation Rights [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r98"
     ]
    },
    "cef_SecurityObligationsOfOwnershipTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SecurityObligationsOfOwnershipTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Security Obligations of Ownership [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r101"
     ]
    },
    "cef_SecurityPreemptiveAndOtherRightsTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SecurityPreemptiveAndOtherRightsTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Security Preemptive and Other Rights [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r100"
     ]
    },
    "cef_SecurityTitleTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SecurityTitleTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Security Title [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r95"
     ]
    },
    "cef_SecurityVotingRightsTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SecurityVotingRightsTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Security Voting Rights [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r97"
     ]
    },
    "cik0000832327_SeniorLoansRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "SeniorLoansRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Loans Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_SeniorSecuritiesAmt": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesAmt",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities Amount"
       }
      }
     },
     "auth_ref": [
      "r138"
     ]
    },
    "cef_SeniorSecuritiesAverageMarketValuePerUnit": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesAverageMarketValuePerUnit",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities Average Market Value per Unit"
       }
      }
     },
     "auth_ref": [
      "r140"
     ]
    },
    "cef_SeniorSecuritiesAveragingMethodNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesAveragingMethodNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities Averaging Method, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r142"
     ]
    },
    "cef_SeniorSecuritiesCvgPerUnit": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesCvgPerUnit",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities Coverage per Unit"
       }
      }
     },
     "auth_ref": [
      "r139"
     ]
    },
    "cef_SeniorSecuritiesHeadingsNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesHeadingsNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities Headings, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r143"
     ]
    },
    "cef_SeniorSecuritiesHighlightsAnnualizedNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesHighlightsAnnualizedNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities Highlights Annualized, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r135",
      "r141"
     ]
    },
    "cef_SeniorSecuritiesHighlightsAuditedNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesHighlightsAuditedNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities Highlights Audited, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r136",
      "r141"
     ]
    },
    "cef_SeniorSecuritiesNoteTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesNoteTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities, Note [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r134",
      "r141"
     ]
    },
    "cef_SeniorSecuritiesTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SeniorSecuritiesTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Senior Securities [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r137"
     ]
    },
    "us-gaap_SharePrice": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://fasb.org/us-gaap/2025",
     "localname": "SharePrice",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Share Price",
        "documentation": "Price of a single share of a number of saleable stocks of a company."
       }
      }
     },
     "auth_ref": []
    },
    "cef_SharePriceTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SharePriceTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Share Price [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r152"
     ]
    },
    "cef_SharePricesNotActualTransactionsTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "SharePricesNotActualTransactionsTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Share Prices Not Actual Transactions [Text Block]"
       }
      }
     },
     "auth_ref": [
      "r153"
     ]
    },
    "cik0000832327_ShareholderActivismRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "ShareholderActivismRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Shareholder Activism Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_ShareholderTransactionExpensesTableTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "ShareholderTransactionExpensesTableTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Shareholder Transaction Expenses [Table Text Block]"
       }
      }
     },
     "auth_ref": [
      "r118"
     ]
    },
    "cik0000832327_ShortSalesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "ShortSalesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Short Sales Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_SmallandMidCapitalizationCompanyRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "SmallandMidCapitalizationCompanyRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Small and Mid-Capitalization Company Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_SovereignDebtRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "SovereignDebtRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Sovereign Debt Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "us-gaap_StatementClassOfStockAxis": {
     "xbrltype": "stringItemType",
     "nsuri": "http://fasb.org/us-gaap/2025",
     "localname": "StatementClassOfStockAxis",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Class of Stock [Axis]",
        "documentation": "Information by the different classes of stock of the entity."
       }
      }
     },
     "auth_ref": [
      "r8",
      "r9",
      "r10",
      "r11",
      "r12",
      "r13",
      "r14",
      "r15",
      "r16",
      "r17",
      "r18",
      "r19",
      "r20",
      "r21",
      "r22",
      "r23",
      "r24",
      "r25",
      "r26",
      "r43",
      "r44",
      "r45",
      "r46",
      "r47",
      "r48",
      "r49",
      "r50",
      "r51",
      "r52",
      "r53",
      "r54",
      "r55",
      "r56",
      "r57",
      "r58",
      "r59",
      "r60",
      "r61",
      "r62",
      "r63",
      "r64",
      "r65",
      "r66",
      "r67",
      "r68",
      "r69",
      "r70",
      "r71",
      "r74",
      "r75",
      "r76",
      "r77",
      "r78",
      "r79",
      "r80",
      "r175",
      "r178",
      "r180",
      "r182"
     ]
    },
    "cik0000832327_StructuredNotesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "StructuredNotesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Structured Notes Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_StructuredSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "StructuredSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Structured Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_SupranationalEntitiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "SupranationalEntitiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Supranational Entities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_TotalAnnualExpensesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "TotalAnnualExpensesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Total Annual Expenses [Percent]"
       }
      }
     },
     "auth_ref": [
      "r131"
     ]
    },
    "cik0000832327_USGovernmentMortgageRelatedSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "USGovernmentMortgageRelatedSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "U.S. Government Mortgage-Related Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_USGovernmentObligationsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "USGovernmentObligationsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "U.S. Government Obligations Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_UnderwritersCompensationPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "UnderwritersCompensationPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Underwriters Compensation [Percent]"
       }
      }
     },
     "auth_ref": [
      "r127"
     ]
    },
    "cik0000832327_UnratedSecuritiesRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "UnratedSecuritiesRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Unrated Securities Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_ValuationRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "ValuationRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Valuation Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_VariableandFloatingRateInstrumentRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "VariableandFloatingRateInstrumentRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Variable and Floating Rate Instrument Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cef_WaiversAndReimbursementsOfFeesPercent": {
     "xbrltype": "percentItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "WaiversAndReimbursementsOfFeesPercent",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Waivers and Reimbursements of Fees [Percent]"
       }
      }
     },
     "auth_ref": [
      "r132"
     ]
    },
    "cef_WarrantsOrRightsCalledAmount": {
     "xbrltype": "monetaryItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "WarrantsOrRightsCalledAmount",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Warrants or Rights, Called Amount"
       }
      }
     },
     "auth_ref": [
      "r112"
     ]
    },
    "cef_WarrantsOrRightsCalledPeriodDate": {
     "xbrltype": "dateItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "WarrantsOrRightsCalledPeriodDate",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Warrants or Rights, Called Period [Date]"
       }
      }
     },
     "auth_ref": [
      "r112"
     ]
    },
    "cef_WarrantsOrRightsCalledTitleTextBlock": {
     "xbrltype": "textBlockItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "WarrantsOrRightsCalledTitleTextBlock",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Warrants or Rights, Called Title"
       }
      }
     },
     "auth_ref": [
      "r112"
     ]
    },
    "cef_WarrantsOrRightsExercisePrice": {
     "xbrltype": "perShareItemType",
     "nsuri": "http://xbrl.sec.gov/cef/2025",
     "localname": "WarrantsOrRightsExercisePrice",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Warrants or Rights, Exercise Price"
       }
      }
     },
     "auth_ref": [
      "r112"
     ]
    },
    "cik0000832327_WarrantsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "WarrantsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Warrants Risk [Member]"
       }
      }
     },
     "auth_ref": []
    },
    "cik0000832327_YieldandRatingsRiskMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.briti/20251231",
     "localname": "YieldandRatingsRiskMember",
     "presentation": [
      "http://xbrl.sec.gov/cef/role/N2"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Yield and Ratings Risk [Member]"
       }
      }
     },
     "auth_ref": []
    }
   }
  }
 },
 "std_ref": {
  "r0": {
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.5-02(22))",
   "SubTopic": "10",
   "Topic": "210",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480566/210-10-S99-1"
  },
  "r1": {
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef",
   "Name": "Accounting Standards Codification",
   "Topic": "505",
   "SubTopic": "10",
   "Section": "50",
   "Paragraph": "3",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481112/505-10-50-3"
  },
  "r2": {
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef",
   "Name": "Accounting Standards Codification",
   "Topic": "505",
   "SubTopic": "10",
   "Section": "50",
   "Paragraph": "4",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481112/505-10-50-4"
  },
  "r3": {
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef",
   "Topic": "210",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.5-02(19))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480566/210-10-S99-1"
  },
  "r4": {
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef",
   "Topic": "210",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.5-02(20))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480566/210-10-S99-1"
  },
  "r5": {
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef",
   "Topic": "210",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.5-02(28))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480566/210-10-S99-1"
  },
  "r6": {
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef",
   "Topic": "942",
   "SubTopic": "210",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.9-03(13))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478546/942-210-S99-1"
  },
  "r7": {
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef",
   "Topic": "942",
   "SubTopic": "210",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.9-03(16))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478546/942-210-S99-1"
  },
  "r8": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Name": "Regulation S-K (SK)",
   "Number": "229",
   "Section": "1402",
   "Paragraph": "a",
   "Publisher": "SEC"
  },
  "r9": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "210",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.5-02(27)(b))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480566/210-10-S99-1"
  },
  "r10": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "210",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.5-02(28))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480566/210-10-S99-1"
  },
  "r11": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "210",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.5-02(29))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480566/210-10-S99-1"
  },
  "r12": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "235",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S50",
   "Paragraph": "1",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480738/235-10-S50-1"
  },
  "r13": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "235",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.4-08(g)(1)(ii))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480678/235-10-S99-1"
  },
  "r14": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "260",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "45",
   "Paragraph": "2",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482689/260-10-45-2"
  },
  "r15": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "260",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "45",
   "Paragraph": "3",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482689/260-10-45-3"
  },
  "r16": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "260",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "45",
   "Paragraph": "60B",
   "Subparagraph": "(d)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482689/260-10-45-60B"
  },
  "r17": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "260",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482662/260-10-50-1"
  },
  "r18": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "272",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482987/272-10-50-1"
  },
  "r19": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "272",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "3",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482987/272-10-50-3"
  },
  "r20": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "323",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "3",
   "Subparagraph": "(c)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481687/323-10-50-3"
  },
  "r21": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1A",
   "Subparagraph": "(SX 210.13-01(a)(4)(i))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480097/470-10-S99-1A"
  },
  "r22": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1A",
   "Subparagraph": "(SX 210.13-01(a)(4)(iv))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480097/470-10-S99-1A"
  },
  "r23": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1A",
   "Subparagraph": "(SX 210.13-01(a)(5))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480097/470-10-S99-1A"
  },
  "r24": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1B",
   "Subparagraph": "(SX 210.13-02(a)(4)(i))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480097/470-10-S99-1B"
  },
  "r25": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1B",
   "Subparagraph": "(SX 210.13-02(a)(4)(iv))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480097/470-10-S99-1B"
  },
  "r26": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1B",
   "Subparagraph": "(SX 210.13-02(a)(5))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480097/470-10-S99-1B"
  },
  "r27": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1B",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1B"
  },
  "r28": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1B",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1B"
  },
  "r29": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1B",
   "Subparagraph": "(c)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1B"
  },
  "r30": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1B",
   "Subparagraph": "(e)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1B"
  },
  "r31": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1B",
   "Subparagraph": "(f)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1B"
  },
  "r32": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1B",
   "Subparagraph": "(h)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1B"
  },
  "r33": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1D",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1D"
  },
  "r34": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1D",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1D"
  },
  "r35": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1D",
   "Subparagraph": "(c)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1D"
  },
  "r36": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1E",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1E"
  },
  "r37": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1E",
   "Subparagraph": "(c)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1E"
  },
  "r38": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1E",
   "Subparagraph": "(d)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1E"
  },
  "r39": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1F",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1F"
  },
  "r40": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1F",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1F"
  },
  "r41": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1F",
   "Subparagraph": "(b)(1)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1F"
  },
  "r42": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1F",
   "Subparagraph": "(b)(2)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1F"
  },
  "r43": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "480",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S45",
   "Paragraph": "1",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479887/480-10-S45-1"
  },
  "r44": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "480",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S45",
   "Paragraph": "2",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479887/480-10-S45-2"
  },
  "r45": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "480",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S50",
   "Paragraph": "1",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479857/480-10-S50-1"
  },
  "r46": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "480",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S50",
   "Paragraph": "2",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479857/480-10-S50-2"
  },
  "r47": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "480",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(01)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480244/480-10-S99-1"
  },
  "r48": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "480",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(04)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480244/480-10-S99-1"
  },
  "r49": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "505",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "13",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481112/505-10-50-13"
  },
  "r50": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "505",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "13",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481112/505-10-50-13"
  },
  "r51": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "505",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "13",
   "Subparagraph": "(h)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481112/505-10-50-13"
  },
  "r52": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "505",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "14",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481112/505-10-50-14"
  },
  "r53": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "505",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "2",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481112/505-10-50-2"
  },
  "r54": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "825",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "28",
   "Subparagraph": "(f)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482907/825-10-50-28"
  },
  "r55": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "3",
   "Subparagraph": "(SX 210.6-03(i)(1))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479886/946-10-S99-3"
  },
  "r56": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "3",
   "Subparagraph": "(SX 210.6-03(i)(2)(i))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479886/946-10-S99-3"
  },
  "r57": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "3",
   "Subparagraph": "(SX 210.6-03(i)(2)(ii))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479886/946-10-S99-3"
  },
  "r58": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "3",
   "Subparagraph": "(SX 210.6-03(i)(2))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479886/946-10-S99-3"
  },
  "r59": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "45",
   "Paragraph": "4",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478009/946-205-45-4"
  },
  "r60": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "2",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-2"
  },
  "r61": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "27",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-27"
  },
  "r62": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "7",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-7"
  },
  "r63": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "7",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-7"
  },
  "r64": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "7",
   "Subparagraph": "(c)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-7"
  },
  "r65": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "7",
   "Subparagraph": "(d)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-7"
  },
  "r66": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "7",
   "Subparagraph": "(e)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-7"
  },
  "r67": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "7",
   "Subparagraph": "(f)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-7"
  },
  "r68": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "7",
   "Subparagraph": "(g)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-7"
  },
  "r69": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "205",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "7",
   "Subparagraph": "(h)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478494/946-205-50-7"
  },
  "r70": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "210",
   "Name": "Accounting Standards Codification",
   "Section": "45",
   "Paragraph": "4",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147477796/946-210-45-4"
  },
  "r71": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "210",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.6-04(16)(a))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479170/946-210-S99-1"
  },
  "r72": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "210",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.6-04(19))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479170/946-210-S99-1"
  },
  "r73": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "210",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "2",
   "Subparagraph": "(SX 210.6-05(4))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479170/946-210-S99-2"
  },
  "r74": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "220",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "3",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478297/946-220-50-3"
  },
  "r75": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "220",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "3",
   "Subparagraph": "(SX 210.6-09(4)(b))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479134/946-220-S99-3"
  },
  "r76": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "505",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478448/946-505-50-1"
  },
  "r77": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "505",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "2",
   "Subparagraph": "(a)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478448/946-505-50-2"
  },
  "r78": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "505",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "2",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478448/946-505-50-2"
  },
  "r79": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "505",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "2",
   "Subparagraph": "(c)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478448/946-505-50-2"
  },
  "r80": {
   "role": "http://www.xbrl.org/2003/role/disclosureRef",
   "Topic": "946",
   "SubTopic": "505",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "2",
   "Subparagraph": "(d)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147478448/946-505-50-2"
  },
  "r81": {
   "role": "http://www.xbrl.org/2003/role/exampleRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1B",
   "Subparagraph": "(d)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481139/470-20-50-1B"
  },
  "r82": {
   "role": "http://www.xbrl.org/2003/role/exampleRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "55",
   "Paragraph": "69B",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481568/470-20-55-69B"
  },
  "r83": {
   "role": "http://www.xbrl.org/2003/role/exampleRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "55",
   "Paragraph": "69C",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481568/470-20-55-69C"
  },
  "r84": {
   "role": "http://www.xbrl.org/2003/role/exampleRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "55",
   "Paragraph": "69E",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481568/470-20-55-69E"
  },
  "r85": {
   "role": "http://www.xbrl.org/2003/role/exampleRef",
   "Topic": "470",
   "SubTopic": "20",
   "Name": "Accounting Standards Codification",
   "Section": "55",
   "Paragraph": "69F",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481568/470-20-55-69F"
  },
  "r86": {
   "role": "http://www.xbrl.org/2003/role/exampleRef",
   "Topic": "835",
   "SubTopic": "30",
   "Name": "Accounting Standards Codification",
   "Section": "55",
   "Paragraph": "8",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482949/835-30-55-8"
  },
  "r87": {
   "role": "http://www.xbrl.org/2003/role/exampleRef",
   "Topic": "946",
   "SubTopic": "830",
   "Name": "Accounting Standards Codification",
   "Section": "55",
   "Paragraph": "12",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147479168/946-830-55-12"
  },
  "r88": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Exchange Act",
   "Number": "240",
   "Section": "12"
  },
  "r89": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Exchange Act",
   "Number": "240",
   "Section": "12",
   "Subsection": "b-2"
  },
  "r90": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form 20-F",
   "Number": "249",
   "Section": "220",
   "Subsection": "f"
  },
  "r91": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form 40-F",
   "Number": "249",
   "Section": "240",
   "Subsection": "f"
  },
  "r92": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form F-3"
  },
  "r93": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2"
  },
  "r94": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10"
  },
  "r95": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "a"
  },
  "r96": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "a",
   "Subparagraph": "1"
  },
  "r97": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "a",
   "Subparagraph": "2"
  },
  "r98": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "a",
   "Subparagraph": "3"
  },
  "r99": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "a",
   "Subparagraph": "4"
  },
  "r100": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "a",
   "Subparagraph": "5"
  },
  "r101": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "a",
   "Subparagraph": "6"
  },
  "r102": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "a",
   "Subparagraph": "Instruction 2"
  },
  "r103": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "b",
   "Subparagraph": "1"
  },
  "r104": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "b",
   "Subparagraph": "2"
  },
  "r105": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "c"
  },
  "r106": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "1",
   "Paragraph": "d"
  },
  "r107": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "2"
  },
  "r108": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "2",
   "Paragraph": "a"
  },
  "r109": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "2",
   "Paragraph": "b"
  },
  "r110": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "2",
   "Paragraph": "c"
  },
  "r111": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "2",
   "Paragraph": "e"
  },
  "r112": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "3"
  },
  "r113": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "5"
  },
  "r114": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "5",
   "Paragraph": "1"
  },
  "r115": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "5",
   "Paragraph": "2"
  },
  "r116": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "5",
   "Paragraph": "3"
  },
  "r117": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 10",
   "Subsection": "5",
   "Paragraph": "4"
  },
  "r118": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1"
  },
  "r119": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 1"
  },
  "r120": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 10",
   "Subparagraph": "a"
  },
  "r121": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 10",
   "Subparagraph": "a, g, h"
  },
  "r122": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 10",
   "Subparagraph": "f"
  },
  "r123": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 10",
   "Subparagraph": "g"
  },
  "r124": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 10",
   "Subparagraph": "i"
  },
  "r125": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 11"
  },
  "r126": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 4"
  },
  "r127": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 5"
  },
  "r128": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 6"
  },
  "r129": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 7",
   "Subparagraph": "a"
  },
  "r130": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 7",
   "Subparagraph": "b"
  },
  "r131": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 8"
  },
  "r132": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 3",
   "Subsection": "1",
   "Paragraph": "Instruction 9"
  },
  "r133": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4"
  },
  "r134": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "1",
   "Paragraph": "Instruction 2"
  },
  "r135": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "1",
   "Paragraph": "Instruction 3"
  },
  "r136": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "1",
   "Paragraph": "Instruction 8"
  },
  "r137": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "3"
  },
  "r138": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "3",
   "Paragraph": "2"
  },
  "r139": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "3",
   "Paragraph": "3",
   "Subparagraph": "Instruction 2"
  },
  "r140": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "3",
   "Paragraph": "5"
  },
  "r141": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "3",
   "Paragraph": "Instruction 1"
  },
  "r142": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "3",
   "Paragraph": "Instruction 4"
  },
  "r143": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 4",
   "Subsection": "3",
   "Paragraph": "Instruction 5"
  },
  "r144": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8"
  },
  "r145": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "2",
   "Paragraph": "b, d"
  },
  "r146": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "3",
   "Paragraph": "a"
  },
  "r147": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "3",
   "Paragraph": "b"
  },
  "r148": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "3",
   "Paragraph": "b",
   "Subparagraph": "1"
  },
  "r149": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "3",
   "Paragraph": "b",
   "Subparagraph": "2"
  },
  "r150": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "3",
   "Paragraph": "b",
   "Subparagraph": "3"
  },
  "r151": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "5",
   "Paragraph": "b"
  },
  "r152": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "5",
   "Paragraph": "b",
   "Subparagraph": "4"
  },
  "r153": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "5",
   "Paragraph": "b",
   "Subparagraph": "Instruction 2"
  },
  "r154": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "5",
   "Paragraph": "b",
   "Subparagraph": "Instruction 3"
  },
  "r155": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "5",
   "Paragraph": "b",
   "Subparagraph": "Instruction 4"
  },
  "r156": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "5",
   "Paragraph": "b",
   "Subparagraph": "Instructions 4, 5"
  },
  "r157": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "5",
   "Paragraph": "c"
  },
  "r158": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-2",
   "Section": "Item 8",
   "Subsection": "5",
   "Paragraph": "e"
  },
  "r159": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-3"
  },
  "r160": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-4"
  },
  "r161": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form N-6"
  },
  "r162": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Form S-3"
  },
  "r163": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Investment Company Act",
   "Number": "270"
  },
  "r164": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Regulation S-T",
   "Number": "232",
   "Section": "313"
  },
  "r165": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "405"
  },
  "r166": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "413",
   "Subsection": "b"
  },
  "r167": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "462",
   "Subsection": "b"
  },
  "r168": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "462",
   "Subsection": "c"
  },
  "r169": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "462",
   "Subsection": "d"
  },
  "r170": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "462",
   "Subsection": "e"
  },
  "r171": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "486",
   "Subsection": "a"
  },
  "r172": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "486",
   "Subsection": "b"
  },
  "r173": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "7A",
   "Section": "B",
   "Subsection": "2"
  },
  "r174": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Section": "8",
   "Subsection": "c"
  },
  "r175": {
   "role": "http://www.xbrl.org/2003/role/recommendedDisclosureRef",
   "Topic": "272",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "45",
   "Paragraph": "3",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147483014/272-10-45-3"
  },
  "r176": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "235",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S50",
   "Paragraph": "1",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480738/235-10-S50-1"
  },
  "r177": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "235",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S50",
   "Paragraph": "4",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480738/235-10-S50-4"
  },
  "r178": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "235",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.4-08(d))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480678/235-10-S99-1"
  },
  "r179": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "235",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.4-08(f))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480678/235-10-S99-1"
  },
  "r180": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "235",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "1",
   "Subparagraph": "(SX 210.4-08(g)(1)(i))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480678/235-10-S99-1"
  },
  "r181": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "235",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "3",
   "Subparagraph": "(SX 210.12-04(a))",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147480678/235-10-S99-3"
  },
  "r182": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "260",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "45",
   "Paragraph": "55",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482689/260-10-45-55"
  },
  "r183": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "405",
   "SubTopic": "40",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1",
   "Subparagraph": "(b)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147477092/405-40-50-1"
  },
  "r184": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "405",
   "SubTopic": "40",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1",
   "Subparagraph": "(c)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147477092/405-40-50-1"
  },
  "r185": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "405",
   "SubTopic": "40",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1",
   "Subparagraph": "(e)(2)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147477092/405-40-50-1"
  },
  "r186": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "505",
   "SubTopic": "10",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "13",
   "Subparagraph": "(h)",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147481112/505-10-50-13"
  },
  "r187": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "835",
   "SubTopic": "30",
   "Name": "Accounting Standards Codification",
   "Section": "45",
   "Paragraph": "2",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482925/835-30-45-2"
  },
  "r188": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "835",
   "SubTopic": "30",
   "Name": "Accounting Standards Codification",
   "Section": "50",
   "Paragraph": "1",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147482900/835-30-50-1"
  },
  "r189": {
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef",
   "Topic": "942",
   "SubTopic": "235",
   "Name": "Accounting Standards Codification",
   "Section": "S99",
   "Paragraph": "2",
   "Publisher": "FASB",
   "URI": "https://asc.fasb.org/1943274/2147477314/942-235-S99-2"
  }
 }
}
