Fair Value - Level 3 Input Roll Forward, Recurring Basis (Details) - Recurring basis - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Roll forward of assets measured using Level 3 inputs on a recurring basis
Balance at the beginning of the year	$ 6,325,237	$ 5,329,147
Purchases and issuances, net	500,158	2,296,087
Capitalization of interest and advances	7,655	32,111
Sales and repayments	(123,090)	(1,134,992)
Mortgage servicing rights resulting from loan sales	286,533	616,302
Changes in fair value included in income arising from:
Changes in instrument specific credit risk	9,543	(5,816)
Other factors	(163,327)	(199,114)
Total changes in fair value included in income	(153,784)	(204,930)
Transfers from Level 3 to Level 2	(365,714)	(1,365,971)
Transfers to real estate acquired in settlement of loans	(52)
Transfers to loans held for sale	(101,918)	(46,226)
Balance at the end of the year	6,375,025	5,521,528
Changes in fair value recognized during the period relating to assets still held at the end of the year	(169,273)	233,466
Excess servicing spread financing
Roll forward of liabilities measured using Level 3 inputs on a recurring basis
Balance at the beginning of the year	2,096
Changes in fair value included in income	(85)
Balance at the end of the year	2,011
Changes in fair value recognized during the period relating to liability still outstanding at the end of the year	(85)
Mortgage servicing liabilities
Roll forward of liabilities measured using Level 3 inputs on a recurring basis
Balance at the beginning of the year		2,816
Changes in fair value included in income		(252)
Balance at the end of the year		2,564
Changes in fair value recognized during the period relating to liability still outstanding at the end of the year		(252)
Mortgage loans held for sale
Roll forward of assets measured using Level 3 inputs on a recurring basis
Balance at the beginning of the year	345,772	1,128,876
Purchases and issuances, net	437,650	2,134,778
Capitalization of interest and advances	7,655	32,111
Sales and repayments	(122,858)	(1,134,992)
Changes in fair value included in income arising from:
Changes in instrument specific credit risk	9,543	(5,816)
Other factors	793	(12,396)
Total changes in fair value included in income	10,336	(18,212)
Transfers from Level 3 to Level 2	(365,714)	(1,365,971)
Transfers to real estate acquired in settlement of loans	(52)
Balance at the end of the year	312,789	776,590
Changes in fair value recognized during the period relating to assets still held at the end of the year	8,413	(17,092)
Interest rate lock commitments
Roll forward of assets measured using Level 3 inputs on a recurring basis
Balance at the beginning of the year	25,844	322,193
Purchases and issuances, net	62,508	161,309
Changes in fair value included in income arising from:
Other factors	72,412	(399,377)
Total changes in fair value included in income	72,412	(399,377)
Transfers to loans held for sale	(101,918)	(46,226)
Balance at the end of the year	58,846	37,899
Changes in fair value recognized during the period relating to assets still held at the end of the year	58,846	37,899
Mortgage servicing rights
Roll forward of assets measured using Level 3 inputs on a recurring basis
Balance at the beginning of the year	5,953,621	3,878,078
Sales and repayments	(232)
Mortgage servicing rights resulting from loan sales	286,533	616,302
Changes in fair value included in income arising from:
Other factors	(236,532)	212,659
Total changes in fair value included in income	(236,532)	212,659
Balance at the end of the year	6,003,390	4,707,039
Changes in fair value recognized during the period relating to assets still held at the end of the year	$ (236,532)	$ 212,659