Derivative Financial Instruments Offsetting Derivative Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Offsetting Assets [Line Items]
Derivative asset, fair value	$ 390,843	$ 144,371
Derivative, Collateral, Obligation to Return Securities	80	802
Derivative, Collateral, Obligation to Return Cash	0	0
Net Amount	390,763	143,569
Derivative liability, gross liability	188,595	76,067
Derivative liability, Collateral, Right to Reclaim Securities	(80)	(802)
Derivative liability, Collateral, Right to Reclaim Cash	(188,515)	(75,265)
Derivative liability, Net Amount	0	0
Interest Rate Swap [Member]
Offsetting Assets [Line Items]
Derivative asset, fair value	390,706	144,179
Derivative, Collateral, Obligation to Return Securities	4	757
Derivative, Collateral, Obligation to Return Cash	0	0
Net Amount	390,702	143,422
Derivative liability, gross liability	188,519	76,022
Derivative liability, Collateral, Right to Reclaim Securities	(4)	(757)
Derivative liability, Collateral, Right to Reclaim Cash	(188,515)	(75,265)
Derivative liability, Net Amount	0	0
Foreign Exchange Contract [Member]
Offsetting Assets [Line Items]
Derivative asset, fair value	137	192
Derivative, Collateral, Obligation to Return Securities	76	45
Derivative, Collateral, Obligation to Return Cash	0	0
Net Amount	61	147
Derivative liability, gross liability	76	45
Derivative liability, Collateral, Right to Reclaim Securities	(76)	(45)
Derivative liability, Collateral, Right to Reclaim Cash	0	0
Derivative liability, Net Amount	$ 0	$ 0