Debt Instruent, Redemption Percentage Of Premium

No definition available.

Name:	onit_DebtInstruentRedemptionPercentageOfPremium
Namespace Prefix:	onit_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Mandatory Call Period

+ References

No definition available.

+ Details

Name:	onit_DebtInstrumentMandatoryCallPeriod
Namespace Prefix:	onit_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Remaining Borrowing Capacity, Committed Amount

+ References

No definition available.

+ Details

Name:	onit_DebtInstrumentRemainingBorrowingCapacityCommittedAmount
Namespace Prefix:	onit_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount

+ References

No definition available.

+ Details

Name:	onit_DebtInstrumentRemainingBorrowingCapacityUncommitedAmount
Namespace Prefix:	onit_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage Of The Limited Liability Company Interest

+ References

No definition available.

+ Details

Name:	onit_PercentageOfTheLimitedLiabilityCompanyInterest
Namespace Prefix:	onit_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Warehouse Facilities, Maximum Term

+ References

No definition available.

+ Details

Name:	onit_WarehouseFacilitiesMaximumTerm
Namespace Prefix:	onit_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: 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

Reference 2: 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

Reference 3: 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

Reference 4: 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

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-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

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-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

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: 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(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: 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

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: 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(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

Name:	us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-1A

Reference 2: 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

Reference 3: 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

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-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

+ Details

Name:	us-gaap_DeferredFinanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 3: 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

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: 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(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: 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)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

Reference 1: 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

Reference 2: 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

Reference 3: 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

Reference 4: 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

Reference 5: 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

Reference 6: 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

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-4

+ Details

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

No definition available.

+ Details

Name:	us-gaap_UnamortizedDebtIssuanceExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_WarehouseAgreementBorrowingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=onit_FinancingAgreementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=onit_SecuritizationNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=onit_MSRFinancingFacilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_MortgageWarehouseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_OLIT2023NotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_OLITNotesFY2022Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_OLITAssetBackedNotesSeries2024HBIMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_AgencyMortgageServicingRightsFinancingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_GinnieMaeMortgageServicingRightsFinancingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_OcwenExcessSpreadCollateralizedNotesSeries2019PLS1ClassAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_OASISSeries20141Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_AgencyMSRFinancingFacilityRevolvingLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_OLITAssetBackedNotesSeries2024HB2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_A70MillionPLSMSRFinancingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=onit_OLIT2023HB1OLIT2024HB1AndOLIT2024HB2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Borrowings - Schedule of Mortgage Loan Warehouse and MSR Financing Facilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Feb. 28, 2025	Jan. 31, 2025	Dec. 31, 2024	Sep. 13, 2024	Feb. 29, 2024	Jun. 15, 2023
Line of Credit Facility [Line Items]
Unamortized debt issuance costs	$ (29.9)			$ (35.4)
Percentage Of The Limited Liability Company Interest	100.00%	100.00%
Mortgage loan financing facilities
Line of Credit Facility [Line Items]
Weighted average interest rate	5.40%			5.46%
Prepaid lender fees, net	$ 1.1			$ 1.0
Secured Debt
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	57.7
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	98.2
Total Financing liabilities	1,136.0			958.0
Unamortized debt issuance costs	0.0			(0.1)
Outstanding borrowings (MSR financing facilities, net)	$ 1,136.0			$ 957.9
Weighted average interest rate	7.27%			7.18%
Secured Debt \| Financing Agreements
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	$ 1,214.4
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	216.9
Total Financing liabilities	$ 1,124.9			$ 1,046.3
Warehouse Facilities, Maximum Term	364 days
Secured Debt \| Securitization Notes
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	$ 0.0
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	0.0
Total Financing liabilities	482.3			517.3
Secured Debt \| Mortgage loan financing facilities
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	1,214.4
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	216.9
Total Financing liabilities	1,607.2			1,563.6
Outstanding borrowings (MSR financing facilities, net)	1,577.4			1,528.2
MSR financing facilities
Line of Credit Facility [Line Items]
Available borrowing capacity	27.0
Mortgage Warehouse Agreement
Line of Credit Facility [Line Items]
Available borrowing capacity	0.0
OLIT 2023 Notes \| Secured Debt \| Securitization Notes
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	0.0
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	0.0
OLIT Notes FY 2022 \| Secured Debt \| Securitization Notes
Line of Credit Facility [Line Items]
Total Financing liabilities	101.2			107.3
OLIT Asset-Backed Notes, Series 2024-HBI \| Secured Debt \| Securitization Notes
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	0.0
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	0.0
Total Financing liabilities	148.8			160.9
Agency Mortgage Servicing Rights Financing Facility \| Secured Debt
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	0.0
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	95.2
Total Financing liabilities	554.8			415.1
Maximum borrowing capacity			$ 650.0	500.0
Ginnie Mae Mortgage Servicing Rights Financing Facility \| Secured Debt
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	54.1
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	0.0
Total Financing liabilities	245.9			244.7
Ocwen Excess Spread-Collateralized Notes, Series 2019/2022-PLS1 Class A \| Secured Debt
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	0.0
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	0.0
Total Financing liabilities	$ 0.0			25.6
Interest rate (as a percent)	5.114%
Debt instrument, face amount	$ 75.0
OASIS Series 2014-1 \| Secured Debt
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	0.0
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	0.0
Total Financing liabilities	21.9			23.1
Agency MSR Financing Facility Revolving Loan
Line of Credit Facility [Line Items]
Prepaid lender fees, net	3.0			2.1
Agency MSR Financing Facility Revolving Loan \| Secured Debt
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	0.0
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	3.1
Total Financing liabilities	246.9			249.5
Maximum borrowing capacity		$ 400.0	$ 250.0
OLIT Asset-Backed Notes, Series 2024-HB2 \| Secured Debt \| Securitization Notes
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	0.0
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	0.0
Total Financing liabilities	232.3			249.1
70 Million PLS MSR Financing Facility \| Secured Debt
Line of Credit Facility [Line Items]
Debt Instrument, Remaining Borrowing Capacity, Uncommited Amount	3.6
Debt Instrument, Remaining Borrowing Capacity, Committed Amount	0.0
Total Financing liabilities	66.4			$ 0.0
Debt instrument, face amount	$ 70.0
OLIT 2023-HB1, OLIT 2024-HB1 and OLIT 2024-HB2 \| Secured Debt
Line of Credit Facility [Line Items]
Total Financing liabilities					$ 330.6	$ 268.6	$ 264.9
Interest rate (as a percent)					5.00%	3.00%	3.00%
Debt Instrument, Mandatory Call Period	3 years
Debt Instruent, Redemption Percentage Of Premium	1.00%