Annual report pursuant to Section 13 and 15(d)

Accounting Policies amortization of leased assets (Details)

v2.4.1.9
Accounting Policies amortization of leased assets (Details) (Leases, Acquired-in-Place [Member], USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Leases, Acquired-in-Place [Member]
     
Acquired Indefinite-lived Intangible Assets [Line Items]      
Amortization of Leased Asset $ 20.3us-gaap_AmortizationOfLeasedAsset
/ wre_ComponentsOfFairValueOfInPlaceLeasesAxis
= us-gaap_LeasesAcquiredInPlaceMember
$ 17.3us-gaap_AmortizationOfLeasedAsset
/ wre_ComponentsOfFairValueOfInPlaceLeasesAxis
= us-gaap_LeasesAcquiredInPlaceMember
$ 19.6us-gaap_AmortizationOfLeasedAsset
/ wre_ComponentsOfFairValueOfInPlaceLeasesAxis
= us-gaap_LeasesAcquiredInPlaceMember