Real Estate Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Significant Acquisitions and Disposals [Line Items]
Gains on disposition of property	$ 5,332	$ 4,397
2017 Dispositions [Member]
Significant Acquisitions and Disposals [Line Items]
Purchase price of real estate	13,000
Disposition closing credits excluded	1,200
Gains on disposition of property	$ 5,300