Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises (Details) - USD ($)	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Securities Financing Transaction
Warehouse facilities collateralized by U.S. Government Sponsored Enterprises	$ 571,705,000	$ 1,050,693,000
Outstanding draws	571,705,000	1,050,693,000
Committed Lines
Securities Financing Transaction
Lines available	1,450,000,000
Warehouse facilities collateralized by U.S. Government Sponsored Enterprises		1,050,693,000
Outstanding draws		1,050,693,000
Uncommitted Lines
Securities Financing Transaction
Lines available	700,000,000
Warehouse facility due October 7, 2022
Securities Financing Transaction
Warehouse facilities collateralized by U.S. Government Sponsored Enterprises	306,457,000	384,571,000
Outstanding draws	$ 306,457,000	384,571,000
Warehouse facility due October 7, 2022 \| LIBOR
Securities Financing Transaction
Basis spread on variable rate	1.30%
Warehouse facility due October 7, 2022 \| Committed Lines
Securities Financing Transaction
Lines available	$ 600,000,000
Warehouse facility due October 7, 2022 \| Committed Lines \| LIBOR
Securities Financing Transaction
Basis spread on variable rate	1.80%
Warehouse facility due October 7, 2022 \| Sublimit Lines
Securities Financing Transaction
Lines available	$ 125,000,000
Warehouse facilities collateralized by U.S. Government Sponsored Enterprises	0
Outstanding draws	0
Warehouse Facility Due June 15, 2022
Securities Financing Transaction
Warehouse facilities collateralized by U.S. Government Sponsored Enterprises	133,153,000	243,659,000
Outstanding draws	$ 133,153,000	243,659,000
Warehouse Facility Due June 15, 2022 \| LIBOR
Securities Financing Transaction
Basis spread on variable rate	1.30%
Warehouse Facility Due June 15, 2022 \| Committed Lines
Securities Financing Transaction
Lines available	$ 450,000,000
Warehouse facility due June 15, 2022
Securities Financing Transaction
Warehouse facilities collateralized by U.S. Government Sponsored Enterprises	0	135,601,000
Outstanding draws	$ 0	135,601,000
Warehouse facility due June 15, 2022 \| LIBOR
Securities Financing Transaction
Basis spread on variable rate	1.30%
Warehouse facility due June 15, 2022 \| Uncommitted Lines
Securities Financing Transaction
Lines available	$ 300,000,000
Warehouse facility due September 25, 2022
Securities Financing Transaction
Warehouse facilities collateralized by U.S. Government Sponsored Enterprises	132,095,000	193,091,000
Outstanding draws	$ 132,095,000	193,091,000
Warehouse facility due September 25, 2022 \| LIBOR
Securities Financing Transaction
Basis spread on variable rate	1.30%
Warehouse facility due September 25, 2022 \| Committed Lines
Securities Financing Transaction
Lines available	$ 400,000,000
Fannie Mae repurchase agreement, open maturity
Securities Financing Transaction
Warehouse facilities collateralized by U.S. Government Sponsored Enterprises	0	93,771,000
Outstanding draws	$ 0	$ 93,771,000
Fannie Mae repurchase agreement, open maturity \| LIBOR
Securities Financing Transaction
Basis spread on variable rate	1.15%
Fannie Mae repurchase agreement, open maturity \| Uncommitted Lines
Securities Financing Transaction
Lines available	$ 400,000,000

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- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

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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.

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Carrying value as of the balance sheet date of the outstanding short-term borrowings under a revolving line of credit used by mortgage bankers to finance the origination or purchase of loans.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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