N-2 |
6 Months Ended |
|---|---|
May 31, 2026 | |
| Cover [Abstract] | |
| Entity Central Index Key | 0001462586 |
| Amendment Flag | false |
| Document Type | N-CSRS |
| Entity Registrant Name | Western Asset Investment Grade Opportunity Trust Inc. |
| Document Period End Date | May 31, 2026 |
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- Definition Boolean flag that is true when the XBRL content amends previously-filed or accepted submission. No definition available.
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- Definition Cover page. No definition available.
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- Definition For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD. No definition available.
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- Definition 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'. No definition available.
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- Definition A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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