Derivatives (Details) $ in Thousands		6 Months Ended
		Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	May. 31, 2014 USD ($) instrument	Apr. 30, 2013 USD ($) instrument
Derivative [Line Items]
Fair value of interest rate hedges recognized in other comprehensive income		$ 12,747
Interest expense		832	$ 351
Interest rate hedges gain (loss) to be reclassified into interest expense over next 12 months		$ 1,729
Forward Swap
Derivative [Line Items]
Number of derivatives | instrument				3	4
Aggregate Notional Amount				$ 225,000	$ 240,000
Fair Value When Terminated	[1]			6,312	3,156
Fair Value Deferred In Other Comprehensive Income	[2]			$ 6,312	$ 3,141

[1] Liability

[2] The amount reported in accumulated other comprehensive income will be reclassified to interest expense as interest payments are made on the related notes payable.