Annual report pursuant to Section 13 and 15(d)

Properties, Net (Details 3)

v3.8.0.1
Properties, Net (Details 3)
$ in Thousands
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Property
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]    
Assets held for sale, net $ 42,226 $ 94,654
Held-for-sale [Member]    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]    
Properties, net 38,670 85,402
Deferred rent receivable 3,237 4,241
Intangible assets on real estate acquisitions, net 0 338
Deferred leasing costs, net 319 3,636
Lease incentives, net 0 1,037
Assets held for sale, net $ 42,226 $ 94,654
Held-for-sale [Member] | Regional Office and Other [Member] | White Marsh, Maryland [Member]    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]    
Number of land parcels held-for-sale | Property   8
Held-for-sale [Member] | Defense/Information Technology Sector [Member] | Northern Virginia Defense/IT [Member]    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]    
Number of land parcels held-for-sale | Property   1