Mortgage Notes Payable (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016		Mar. 31, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Repayments of Notes Payable	$ 84,219		$ 1,155
John Marshall II Member
Debt Instrument [Line Items]
Repayments of Notes Payable	50,900
Six Fifty North Glebe Road [Member]
Debt Instrument [Line Items]
Loans Payable	$ 32,215	[1]		$ 32,214

[1] The mortgage notes payable balance as of March 31, 2016 is eliminated in consolidation due to the purchase of the loan by Washington REIT in January 2016.