Derivative Financial Instruments - Notional Amounts and Fair Values (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Derivatives designated as hedging instruments | Interest rate swaps
Notional amounts and fair values of derivatives
Notional Amount	$ 23,545	$ 41,317
Derivatives designated as hedging instruments | Interest rate swaps | Included in other assets
Notional amounts and fair values of derivatives
Asset Derivatives		31
Derivatives designated as hedging instruments | Interest rate swaps | Included in other liabilities
Notional amounts and fair values of derivatives
Liability Derivatives	(927)	(44)
Derivatives Not Designated as Hedging Instruments | Interest rate swaps
Notional amounts and fair values of derivatives
Notional Amount	2,749,924	2,269,247
Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Included in other assets
Notional amounts and fair values of derivatives
Asset Derivatives	85,883	12,305
Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Included in other liabilities
Notional amounts and fair values of derivatives
Liability Derivatives		(12,007)
Derivatives Not Designated as Hedging Instruments | Funding Swap (Visa Derivative)
Notional amounts and fair values of derivatives
Notional Amount	69,378	62,039
Derivatives Not Designated as Hedging Instruments | Funding Swap (Visa Derivative) | Included in other liabilities
Notional amounts and fair values of derivatives
Liability Derivatives	(584)	(2,607)
Derivatives Not Designated as Hedging Instruments | Foreign exchange contracts
Notional amounts and fair values of derivatives
Notional Amount	2,514	1,191
Derivatives Not Designated as Hedging Instruments | Foreign exchange contracts | Included in other liabilities
Notional amounts and fair values of derivatives
Liability Derivatives	$ (31)	$ (34)