Derivative Financial Instruments Fair Value Gains and Losses on Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Net fair value gains (losses) on derivative financial instruments	$ 5,056	$ 831	$ (822)
Mortgage Banking Derivatives
Derivatives, Fair Value [Line Items]
Net fair value gains (losses) on derivative financial instruments	4,974	689	(748)
Interest Rate Swap
Derivatives, Fair Value [Line Items]
Net fair value gains (losses) on derivative financial instruments	70	122	1
Foreign Exchange Contract
Derivatives, Fair Value [Line Items]
Net fair value gains (losses) on derivative financial instruments	$ 12	$ 20	$ (75)