Mortgage Servicing - Schedule of Components of Servicing and Subservicing Fees (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Participating Mortgage Loans [Line Items]
Servicing fee	$ 107.3	$ 91.9	$ 306.6	$ 274.0
Subservicing fee	22.0	26.7	68.5	81.0
MAV - Subservicing fee			4.5	6.1
MAV			39.8	49.9
Rithm			56.6	56.9
Servicing and Subservicing fees, total	162.1	154.0	475.9	467.9
Late charges	9.4	8.8	28.9	25.5
Reverse subservicing ancillary fees	2.7	5.2	9.2	18.1
Custodial accounts (float earnings)	36.4	35.4	95.8	94.5
Other, net	6.8	7.7	22.3	20.6
Total ancillary income	55.3	57.1	156.2	158.6
Servicing and subservicing fees	217.5	211.1	632.1	626.5
Servicing and Subservicing Fees, Owned MSR	181.9	173.5	524.1	507.6
Servicing and Subservicing Fees, Transferred MSR	35.6	37.6	108.0	118.9
Ancillary fees - Transferred MSR	4.2	4.4	$ 11.6	$ 12.1
MAV Asset Vehicle LLC
Participating Mortgage Loans [Line Items]
MAV - Subservicing fee	1.5	2.2
MAV	13.1	14.1
Rithm Capital Corp . and others
Participating Mortgage Loans [Line Items]
Rithm	$ 18.4	$ 19.1

Ancillary fees - Transferred MSR

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- Definition

All amounts that, per contract, are due in exchange for servicing or subservicing the financial asset.

+ References

No definition available.

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- Definition

Contractually specified servicing fees collected on behalf of counterparty.

+ References

No definition available.

+ Details

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- Definition

All amounts that, per contract, are due to the subservicer in exchange for subservicing the financial asset and would no longer be received by a subservicer if the owners of the servicing rights were to exercise their authority under the contract to shift the subservicing to another servicer.

+ References

No definition available.

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- Definition

Contractually Specified Subservicing Fees Collected on Behalf of Counterparty

+ References

No definition available.

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- Definition

Represents amount related to interest earned on unremitted loan payments held in custodial accounts, are due to the servicer in exchange for servicing the financial asset.

+ References

No definition available.

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- Definition

Reverse subservicing ancillary income.

+ References

No definition available.

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- Definition

This represents the amount of the fee earned, generally expressed as a percent of UPB, from the borrowers’ payments. Also includes late fees, prepayment penalties, float earnings and other ancillary fees.

+ References

No definition available.

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- Definition

Servicing and Subservicing Fees, Owned MSR

+ References

No definition available.

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Servicing and Subservicing Fees, Transferred MSR

+ References

No definition available.

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- Definition

Servicing fee collected on mortgage servicing rights for which rights have been sold to NRZ.

+ References

No definition available.

+ Details

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- Definition

All amounts that are due to the servicer of a financial asset, excluding contractually specified servicing fees and late fees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-2

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

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- Definition

Amount of contractually specified servicing fee, late fee, and ancillary fee recognized as income for servicing asset and servicing liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-2

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- Definition

All amounts that are due to the servicer of a financial asset as a result of the debt holder not meeting the monthly payment terms.

+ References

+ Details

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- 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.

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