Derivative and Hedging Activities (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Feb. 09, 2018 USD ($)	Dec. 31, 2017 USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Interest Rate Derivative Assets, at Fair Value	$ 7,700			$ 2,200
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	200
Unrealized Gain on cash flow hedging activities	3,601	$ 0
Derivative Instruments, Gain Recognized in Other Comprehensive Income (Loss), Effective Portion	3,600
Interest Rate Derivative Liabilities, at Fair Value	2,400			500
Derivative Assets (Liabilities), at Fair Value, Net	5,300
Interest Rate Cap [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount		$ 175,000
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest Rate Derivative Assets, at Fair Value	7,700			2,200
Interest Rate Derivative Liabilities, at Fair Value	2,400			$ 500
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	$ 400,000		$ 200,000
Number of Interest Rate Derivatives Held	5		2