Unfunded Loan Commitments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Credit Loss [Abstract]
Contractual obligation	$ 1,800,000
Allowance:
Beginning balance	110,044	$ 2,481	$ 2,165
Provisions for unfunded loan commitments	232,822	311,659	5,937
Other provision items	31,502	954	596
Transfer - funded loans	(301,655)	(320,808)	(6,217)
Ending balance	72,713	110,044	2,481
Unfunded Commitments
Beginning balance	1,673,018	1,910,603	2,010,744
Provision/New commitments - net	5,512,841	5,070,175	5,513,790
Other provision items	0	0	0
Transfer - funded loans	(5,408,883)	(5,307,760)	(5,613,931)
Ending balance	$ 1,776,976	1,673,018	1,910,603
Cumulative Effect, Period of Adoption, Adjustment
Allowance:
Beginning balance		115,758
Ending balance			115,758
Unfunded Commitments
Beginning balance		0
Ending balance			0
Cumulative Effect, Period Of Adoption, Adjusted Balance
Allowance:
Beginning balance		118,239
Ending balance			118,239
Unfunded Commitments
Beginning balance		$ 1,910,603
Ending balance			$ 1,910,603