XML 123 R100.htm IDEA: XBRL DOCUMENT v3.24.3

Commitments - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Other Commitments [Line Items]
Threshold of outstanding principal balance on maximum claim amount (as a percent)	98.00%
Floating Rate Reverse Mortgage Loans
Other Commitments [Line Items]
Additional borrowing capacity to borrowers	$ 1,800.0	$ 1,800.0
Funded amount in connection with reverse mortgage loans	179.1
Forward Mortgage Loan Interest Rate Lock Commitments
Other Commitments [Line Items]
Short-term commitments to lend	1,700.0
Reverse loans IRLCs
Other Commitments [Line Items]
Short-term commitments to lend	$ 26.9
Customer Concentration Risk | Servicing And Subservicing Fees Benchmark | Rithm
Other Commitments [Line Items]
Concentration risk (percent)	16.00%
Concentration Risk, Amount	$ 38.8
Customer Concentration Risk | Servicing And Subservicing Fees Benchmark | Rithm Capital Corp
Other Commitments [Line Items]
Concentration Risk, Amount	$ 73.5
Customer Concentration Risk | Servicing And Subservicing Fees Benchmark | MAV Asset Vehicle LLC
Other Commitments [Line Items]
Concentration risk (percent)	12.00%
Concentration Risk, Amount	$ 56.0
Customer Concentration Risk | Unpaid Principal Balance | Rithm Capital Corp
Other Commitments [Line Items]
Concentration risk (percent)	14.00%
Concentration Risk, Amount	$ 42,200.0
Customer Concentration Risk | Unpaid Principal Balance | MAV Asset Vehicle LLC
Other Commitments [Line Items]
Concentration risk (percent)	14.00%
Customer Concentration Risk | Loan Count | Rithm Capital Corp
Other Commitments [Line Items]
Concentration risk (percent)	25.00%
Customer Concentration Risk | Loan Count | MAV Asset Vehicle LLC
Other Commitments [Line Items]
Concentration risk (percent)	11.00%
Customer Concentration Risk | Delinquent Loans | Rithm
Other Commitments [Line Items]
Concentration risk (percent)	64.00%
Customer Concentration Risk | Servicing and Subservicing Portfolio Benchmark | MAV Asset Vehicle LLC
Other Commitments [Line Items]
Concentration Risk, Amount	$ 41,900.0
Customer Concentration Risk | Pledged MSR Liability Expense Benchmark | Rithm
Other Commitments [Line Items]
Concentration Risk, Amount	27.6
Customer Concentration Risk | Pledged MSR Liability Expense Benchmark | MAV Asset Vehicle LLC
Other Commitments [Line Items]
Concentration Risk, Amount	$ 42.1

X

- Definition

Additional borrowing capacity to borrowers.

+ References

No definition available.

+ Details

Name:	onit_AdditionalBorrowingCapacityToBorrowers
Namespace Prefix:	onit_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Concentration Risk, Amount

+ References

No definition available.

+ Details

Name:	onit_ConcentrationRiskAmount
Namespace Prefix:	onit_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Funded amount in connection with reverse mortgage loans.

+ References

No definition available.

+ Details

Name:	onit_FundedAmountInConnectionWithReverseMortgageLoans
Namespace Prefix:	onit_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Short-term commitments to lend.

+ References

No definition available.

+ Details

Name:	onit_ShortTermCommitmentsToLend
Namespace Prefix:	onit_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Threshold percentage of outstanding principal balance on maximum claim amount.

+ References

No definition available.

+ Details

Name:	onit_ThresholdPercentageOfOutstandingPrincipalBalanceOnMaximumClaimAmount
Namespace Prefix:	onit_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-21

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-20

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482861/275-10-50-18

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482861/275-10-50-20

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

X

- 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

No definition available.

+ Details

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

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=onit_FloatingRateReverseMortgageLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=onit_ForwardMortgageLoanInterestRateLockCommitmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=onit_ReverseMortgageLoanInterestRateLockCommitmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=onit_ServicingAndSubservicingFeesBenchmarkMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=onit_NewResidentialInvestmentCorpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=onit_RithmCapitalCorpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=onit_MAVAssetVehicleLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=onit_UnpaidPrincipalBalanceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=onit_LoanCountMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=onit_DelinquentLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=onit_ServicingAndSubservicingPortfolioBenchmarkMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=onit_PledgedMSRLiabilityExpenseBenchmarkMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: