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, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reconciliation for all assets and (liabilities) measured at fair value on a recurring basis using significant unobservable inputs (Level 3) [Roll Forward]
Beginning balance	$ 17,894	$ 21,848	$ 21,400	$ 15,699
Total gains (losses) realized and unrealized [Abstract]
Included in results of operations	(3,145)	(198)	(9,258)	694
Included in other comprehensive income (loss)	0	0	0	0
Purchases, issuances, settlements, maturities and calls	2,157	1,501	4,764	6,758
Transfers in and/or out of Level 3	0	0	0	0
Ending balance	16,906	23,151	16,906	23,151
Amount of total gains (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	$ (3,145)	$ (198)	$ (9,258)	$ 694