Derivative Instruments - Derivatives Not Designated as Hedging Instruments (Details) - Derivatives not designated as hedges - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	$ 1,717	$ (4,278)	$ 28,250	$ (9,372)
Interest rate contracts | Other noninterest income
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	(477)	(773)	1,185	(1,260)
Risk participation agreements | Other noninterest expense
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	49	38	4,375	(283)
Forward foreign exchange contracts | Other noninterest expense
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	(7,492)	(3,830)	11,221	(8,609)
Interest rate lock commitments | Net gains on sales of loans and leases
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	5,394	287	15,772	780
Forward loan sales commitments | Net gains on sales of loans and leases
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	4,243	0	(4,302)	0
Swap agreement | Other noninterest income
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	$ 0	$ 0	$ (1)	$ 0