Fair Value Disclosures, Reconciliation for all Assets Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3) (Details) - Capitalized Mortgage Loan Servicing Rights [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reconciliation for all assets and (liabilities) measured at fair value on a recurring basis using significant unobservable inputs (Level 3) [Roll Forward]
Beginning balance	$ 13,773	$ 17,894	$ 19,171	$ 21,400
Total gains (losses) realized and unrealized [Abstract]
Included in results of operations	(2,387)	(3,145)	(14,028)	(9,258)
Included in other comprehensive income	0	0	0	0
Purchases, issuances, settlements, maturities and calls	4,017	2,157	10,260	4,764
Transfers in and/or out of Level 3	0	0	0	0
Ending balance	15,403	16,906	15,403	16,906
Amount of total losses for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets and liabilities still held at September 30	$ (2,387)	$ (3,145)	$ (14,028)	$ (9,258)