Reverse Mortgages - Schedule of Reverse Mortgage Revenue, Net (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Receivables [Abstract]
Gain on new originations	$ 5.5	$ 4.4	$ 16.5	$ 13.9
Net interest income (servicing fee)	6.2	5.9	18.2	17.7
Other change in fair value of securitized loans held for investment and HMBS-related borrowings, net	5.7	(12.0)	5.0	(13.8)
Change in fair value included in earnings, net	17.3	(1.7)	39.7	17.8
Loan fees and other	0.7	1.3	2.2	3.7
Gain (loss) on reverse loans held for investment and HMBS-related borrowings, net	18.0	(0.4)	41.9	21.5
Change in fair value	162.4	120.6	496.8	316.3
Change in fair value	$ (145.0)	$ (122.4)	$ (457.1)	$ (298.5)

Fee and Commissions, Reverse Mortgage Banking

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Change in fair value related to home equity conversion mortgage-backed securities related borrowings accounted for as a financing.

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Loands Held For Investment, Reverse Mortgage, Other Change In Fair Value

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Change in fair value of loans held for investment, reverse mortgages during the period.

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- Definition

Net interest income (servicing fee) - Reverse mortgages

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No definition available.

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- Definition

Amount of gain (loss) recognized in income from asset and liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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A gain (loss) realized on a transfer, accounted for as a sale, of all or a portion of financial assets in which the transferor surrenders control and receives consideration other than a beneficial interest in the assets transferred. Reflects the amount of sales proceeds in excess of, or deficient from, the sum of the carrying amounts of transferred financial assets plus transaction costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)(3)
-Publisher FASB
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-Topic 230
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of interest and fee income from loans classified as other.

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