Fair Value Measurements, Fair Value of Assets Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Assets measured on recurring basis, unobservable input reconciliation [Roll Forward]
Loans, impaired, outstanding balance	$ 217,000,000,000		$ 224,000,000
Loans, impaired, specific reserve	31,000,000,000		$ 39,000,000
Real estate owned, change in fair value	0	$ 0
Mortgage Banking Derivatives, Net [Member]
Assets measured on recurring basis, unobservable input reconciliation [Roll Forward]
Beginning balance	1,835,000	898,000
Mortgage derivative gain (loss), net		1,238,000
Ending balance		$ 2,136,000
Mortgage Banking Derivatives, Net [Member] | Recurring [Member]
Assets measured on recurring basis, unobservable input reconciliation [Roll Forward]
Mortgage derivative gain (loss), net	(3,282,000)
Ending balance	$ (1,447,000)