Mortgage Banking Activities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Other income, net	$ 12,018	$ 4,188	$ 19,257
Mortgage Banking Activities, Net	235,744	78,472	87,266
Residential Mortgage Banking Activities, Net
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Other income, net	5,418	(6,652)	1,735
Mortgage Banking Activities, Net	127,151	3,721	47,743
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	83,733	41,284	63,527
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	(352)	(4,535)	0
Residential Mortgage Banking Activities, Net \| Risk management derivatives, net
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Changes in fair value of risk management derivatives	38,352	(26,376)	(17,519)
Business Purpose Mortgage Banking
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Other income, net	33,760	18,642	16,205
Mortgage Banking Activities, Net	108,593	74,751	39,523
Business Purpose Mortgage Banking \| Risk management derivatives, net
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Changes in fair value of risk management derivatives	2,708	(21,403)	1,796
Business Purpose Mortgage Banking \| Single-family rental loans, held-for-sale
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	63,872	82,510	17,004
Business Purpose Mortgage Banking \| Bridge loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	$ 8,253	$ (4,998)	$ 4,518

Increase (Decrease) in Fair Value Adjustments on Assets

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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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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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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

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- Definition

Amount of revenue and income classified as other.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.4)
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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