Derivatives and Hedging Activities - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	May 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Unrealized gain (loss) on cash flow hedges, net	$ 1,754,000	$ 0	$ (2,992,000)	$ 0
Ineffective portion of the change in fair value derivatives			0
Interest expense	45,544,000	$ 42,839,000	134,998,000	$ 72,314,000
Interest rate swaps
Derivative [Line Items]
Weighted Average Fixed Rate					1.844%
Notional Amount					$ 1,200,000,000
Interest expense	2,000,000		7,400,000
Designated as Hedging Instrument | Interest rate swaps
Derivative [Line Items]
Weighted Average Fixed Rate						1.825%
Notional Amount	1,200,000,000		1,200,000,000			$ 500,000,000
Fair Value Asset (Liability)	$ (1,335,000)		$ (1,335,000)			$ 1,900,000