Derivative Instruments - Derivatives Not Designated as Hedging Instruments (Details) - Not Designated as Hedges - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	$ (29,140)	$ 23,830	$ (16,400)
Interest rate contracts
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	(17,300)
Termination Derivative	1,100,000
Interest rate contracts | Other noninterest income
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	(18,240)	(440)	(230)
Risk participation agreements | Other noninterest income
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	123	31	(38)
Forward foreign exchange contracts | Other non-interest expense
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	(10,209)	23,707	(15,748)
Interest rate lock commitments | Net (losses) gains on sales of loans and leases
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	(573)	806	(73)
Forward loan sales commitments | Net (losses) gains on sales of loans and leases
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	(172)	0	0
Other contracts | Other noninterest income
Derivative instruments, gain (loss)
Net gain (loss) of derivatives included in the Consolidated Statements of Income	$ (69)	$ (274)	$ (311)