Mortgage Servicing Rights - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Servicing Assets at Fair Value [Line Items]
MSR UPB of underlying loans	$ 11,700.0	$ 22,500.0	$ 23,500.0	$ 31,200.0
Remaining receivable balance	31.0		31.0		$ 22.0
Ancillary income associated with the Company's MSR portfolio	80.1	66.8	157.3	125.8
Early payoff fee income	4.9	6.1	11.4	10.5
Servicing advances, net	81.0		81.0		$ 108.0
Servicing Contracts
Servicing Assets at Fair Value [Line Items]
Gain (loss) on MSR sales	$ (3.5)	$ 6.6	$ 8.5	$ 6.3

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

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

The increase (decrease) in the fair value of servicing assets that are subsequently measured at fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-3

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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 860
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147481229/860-50-50-3

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
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- Definition

Receivable balance related to holdbacks on sales for pending servicing transfers

+ References

No definition available.

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- Definition

The unpaid principal balance of loans underlying sales of mortgage servicing rights

+ References

No definition available.

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- Definition

Servicing advances, net

+ References

No definition available.

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- Definition

Servicing Assets, Early Payoff Fee Income

+ References

No definition available.

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