Derivative Instruments, Hedging Activities and Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Average cap interest rate (as percent)	3.69%
Interest rate fair value hedge liability at fair value	$ 3,500	$ 2,400
Gain (loss) reclassified from AOCI into income, effective portion, net	(800)	(2,500)	$ (4,800)
Interest expense	66,785	65,702	$ 65,577
Increase As Hedged Forecasted Interest Payments Occur
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest expense	1,300
Prepaid Expenses and Other Current Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest rate fair value hedge asset at fair value	3,600	3,100
Accounts Payable and Accrued Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest rate fair value hedge liability at fair value	7,100	700
Accrued Interest
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest rate fair value hedge liability at fair value	100	$ 100
Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	$ 391,200