Summary of Significant Accounting Policies - Construction in Progress (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Construction in progress	$ 92,698	$ 83,516
Park Van Ness
Property, Plant and Equipment [Line Items]
Construction in progress	86,079	77,245
Other
Property, Plant and Equipment [Line Items]
Construction in progress	$ 6,619	$ 6,271