Accumulated Other Comprehensive Income (Amounts Reclassified from AOCI) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Acceleration of 2020 Swap	$ 32,848	$ 28,569	$ 27,749
Total	32,030	71,451	27,382
Interest Rate Swap | Reclassification out of Accumulated Other Comprehensive Loss | Derivative Instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest Expense - Amortization of IRPAs	410	233	96
Interest Expense - Settlement Payments	6,516	(1,217)	109
Acceleration of 2020 Swap	201	0	0
Total	$ 7,127	$ (984)	$ 205