Derivatives (Offsetting Derivative Assets and Liabilities Subject to Master Netting Arrangements) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Gross Amounts Recognized, Derivative Assets	$ 27,938	$ 16,167
Gross Amounts Offset in the Statement of Financial Position, Derivative Assets	(27,915)	(12,842)
Net Amounts Presented in the Statement of Financial Position, Derivative Assets	23	3,325
Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments, Derivative Assets	23	1,846
Gross Amounts Not offset in the Statement of Financial Position - Cash Collateral, Derivative Assets	0	0
Net Amounts Presented in the Statement of Financial Position, Derivative Assets	0	1,479
Gross Amounts Recognized, Derivative Liabilities	56,523	23,811
Gross Amounts Offset in the Statement of Financial Position, Derivative Liabilities	(44,570)	(21,651)
Net Amounts Presented in the Statement of Financial Position, Derivative Liabilities	11,953	2,160
Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments, Derivative Liabilities	23	1,846
Gross Amounts Not Offset in the Statement of Financial Position - Cash Collateral, Derivative Liabilities	35,113	2,871
Gross Amounts Not Offset in the Statement of Financial Position - Net Amount, Derivatives Liabilities	$ (23,183)	$ (2,557)