Derivative Instruments - Gains (Losses) On Derivative Financial Instruments (Details) - Not designated as hedging instruments: - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	$ 2,070	$ 4,032	$ 23,925	$ 8,945
Interest rate contracts | Included in interest income on loans
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	451	950	1,710	2,985
Interest rate lock commitments | Included in mortgage banking income
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	(1,135)	(444)	23,610	2,954
Forward commitments | Included in mortgage banking income
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	$ 2,754	$ 3,526	$ (1,395)	$ 3,006