Derivative Instruments Derivative Instruments (Summary of Cash Flow Hedge Activity) (Details) - Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Summary of Cash Flow Hedge Activity [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	$ 84,617	$ 3,027
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	107,621	10,873
Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), before Adjustments and Tax	(23,004)	(7,846)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	(268)	(678)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	763	0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	(1,031)	(678)
Interest Rate Floor [Member]
Summary of Cash Flow Hedge Activity [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	84,617	3,027
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	107,621	10,873
Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), before Adjustments and Tax	(23,004)	(7,846)
Interest and Fee Income on Loans [Member] | Interest Rate Floor [Member]
Summary of Cash Flow Hedge Activity [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	(268)	(678)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	763	0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	$ (1,031)	$ (678)