Derivative Financial Instruments Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	$ 12,390	$ 4,779
Derivative Asset	343,890	133,158
Derivative Liability, Fair Value, Amount Offset Against Collateral	12,390	4,779
Derivative Liability	772	7,163
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	196	299
Derivative Asset, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election	196	432
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	1,041	329
Derivative Liability, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election	1,134	389
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	17,568	6,710
Derivative Asset, Fair Value, Gross Asset	44,549	13,012
Derivative Asset, Fair Value, Amount Offset Against Collateral	44,549	12,879
Derivative Asset	0	133
Derivative Liability, Fair Value, Amount Offset Against Collateral	17,475	6,650
Derivative Liability	$ 93	$ 60