Derivative Financial Instruments - Cash Flow Hedges and Contingent Features (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Cash Flow Hedges of Interest Rate Risk
Total interest expense presented in the Consolidated Statements of Operations in which the effects of cash flow hedges are recorded	$ 15,928,000	$ 14,053,000	$ 46,125,000	$ 39,080,000
Interest Rate Swaps
Cash Flow Hedges of Interest Rate Risk
Additional amount reclassified from accumulated other comprehensive income (loss) as a increase (decrease) to interest expense over the next twelve months	16,600,000		16,600,000
Income (loss) recognized in accumulated other comprehensive loss on interest rate swaps	169,000	(5,913,000)	(36,167,000)	(26,715,000)
Income (loss) reclassified from accumulated other comprehensive loss into income as interest expense	(4,758,000)	522,000	(8,894,000)	2,726,000
Total interest expense presented in the Consolidated Statements of Operations in which the effects of cash flow hedges are recorded	15,928,000	$ 14,053,000	46,125,000	$ 39,080,000
Assets Needed for Immediate Settlement, Aggregate Fair Value	$ 46,900,000		$ 46,900,000