Fair Value - Changes in Fair Value, Fair Value Option, Recurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Liability [Member]
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	$ 148,102	$ 32,111	$ 26,785
Liability [Member] | Net gains on loans held for sale at fair value
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings			26,785
Liability [Member] | Net loan servicing fees
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	148,102	32,111
Excess servicing spread financing
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	(1,037)	24,970	9,256
Excess servicing spread financing | Net gains on loans held for sale at fair value
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings			9,256
Excess servicing spread financing | Net loan servicing fees
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	(1,037)	24,970
Mortgage servicing liabilities
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	149,139	7,141	17,529
Mortgage servicing liabilities | Net gains on loans held for sale at fair value
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings			17,529
Mortgage servicing liabilities | Net loan servicing fees
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	149,139	7,141
Assets
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	2,003,273	1,390,180	(194,248)
Assets | Net gains on loans held for sale at fair value
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	2,568,318	2,899,314	(1,006,143)
Assets | Net loan servicing fees
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	(565,045)	(1,509,134)	811,895
Mortgage loans held for sale
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	2,568,318	2,899,314	811,895
Mortgage loans held for sale | Net gains on loans held for sale at fair value
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	2,568,318	2,899,314
Mortgage loans held for sale | Net loan servicing fees
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings			811,895
Mortgage servicing rights at fair value
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	(565,045)	(1,509,134)	(1,006,143)
Mortgage servicing rights at fair value | Net gains on loans held for sale at fair value
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings			$ (1,006,143)
Mortgage servicing rights at fair value | Net loan servicing fees
Net gains (losses) from changes in estimated fair values included in earnings for financial statement items carried at estimated fair value
Total gains (losses) from changes in estimated fair values included in earnings	$ (565,045)	$ (1,509,134)