Accumulated Other Comprehensive Income (Amounts Reclassified from AOCI) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Settlement Gain on Derivative Instruments	$ 0	$ 0	$ 1,896
Interest Expense - Amortization of IRPAs	50,273	50,775	57,199
Total	71,451	27,382	71,029
Interest Rate Swap | Reclassification out of Accumulated Other Comprehensive Loss | Derivative Instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest Expense - Amortization of IRPAs	233	96	205
Interest Expense - Settlement Payments	(1,217)	109	4,336
Total	$ (984)	$ 205	$ 4,541