Mortgage Banking Activities, Net (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Other income, net	$ 2,346	$ 4,027	$ 11,060	$ 17,016
Mortgage banking activities, net	19,440	16,535	52,663	2,833
Residential Mortgage Banking Activities, Net
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Other income, net	107	467	1,422	5,496
Mortgage banking activities, net	8,964	2,158	19,390	(7,694)
Residential Mortgage Banking Activities, Net \| Residential loans, held-for-sale, at fair value
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	(2,819)	(22,776)	5,272	(125,012)
Residential Mortgage Banking Activities, Net \| Trading securities
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	(482)	148	2,188	4,249
Residential Mortgage Banking Activities, Net \| Risk management derivatives
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Risk management derivatives	12,158	24,319	10,508	107,573
Business Purpose Mortgage Banking Activities, Net
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Other income, net	4,004	9,648	13,956	36,214
Mortgage banking activities, net	10,476	14,377	33,273	10,527
Business Purpose Mortgage Banking Activities, Net \| Single-family rental loans, at fair value
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	1,600	(19,306)	13,214	(84,493)
Business Purpose Mortgage Banking Activities, Net \| BPL bridge loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	1,438	(9)	4,808	2,242
Business Purpose Mortgage Banking Activities, Net \| Risk management derivatives
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Risk management derivatives	$ 3,434	$ 24,044	$ 1,295	$ 56,564

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- Definition

The net income attributable to mortgage banking activities. This includes market valuations related to residential and commercial loans, Sequoia IOs, and mortgage banking derivatives, as well as realized gains or losses associated with mortgage loan sales.

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479851/948-310-S99-1

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Amount of unrealized gain (loss) related to the fair value of price risk derivatives designated as fair value hedging instruments, as offset by the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4C

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Amount of revenue and income classified as other.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14(Column E)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480032/946-320-S99-6

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-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14(Column E)(Footnote 4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480032/946-320-S99-6

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-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14(Column E)(Footnote 6)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480032/946-320-S99-6

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-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

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-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.6-07(1)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

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