Derivative Financial Instruments and Hedging Activities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Derivatives	$ 6,800	$ 1,700
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	700
Interest Rate Derivative Assets, at Fair Value	$ 0	2,200
Description of Derivative Activity Volume	400
Derivative, Number of Instruments Held	4
Derivative, notional amount entered in the year	$ 500,000
Interest Rate Derivative Liabilities, at Fair Value	7,400	500
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	400	0
Payments for (Proceeds from) Hedge, Financing Activities	15,905	0	$ 0
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	0	2,200
Interest Rate Derivative Liabilities, at Fair Value	7,400	500
Interest Rate Cap [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		$ 200,000
Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 300,000
Number of Interest Rate Derivatives Held	2	3
Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	$ 0	$ 2,200
Interest Rate Derivative Liabilities, at Fair Value	$ 7,400	$ 500