Derivative Financial Instruments - Effects of Derivative Instruments on Statements of Operations (Details) - Derivatives not Designated as Hedging Instruments [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Mortgage Banking, Net [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) recognized in mortgage banking, net	$ (1,612)	$ 74	$ (12,424)	$ 45,955
Bank Card and Other Fees [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) recognized in bank card and other fees	$ 217	$ 234	$ 1,152	$ (1,502)