Subsequent Events - Line of Credit, Agreements, and Waivers (Detail) (USD $)	0 Months Ended
	Jun. 30, 2014	Dec. 23, 2014	Oct. 17, 2014	Apr. 04, 2014	Dec. 31, 2013		Sep. 15, 2013	Dec. 31, 2012		Nov. 12, 2014	Dec. 23, 2013	Jun. 12, 2014
Subsequent Event [Line Items]
Face Amount of Mortgages					$ 0
Real Estate Investment Property, at Cost					7,459,142,000	[1]		1,875,615,000	[1]
Carrying Amount of Mortgages					1,301,114,000	[1]		265,118,000	[1]
Common stock, par value				$ 0.01	$ 0.01	[1]	$ 0.01	$ 0.01	[1]
Line of credit facility, maximum borrowing capacity					1,900,000,000
Mortgages [Member]
Subsequent Event [Line Items]
Carrying Amount of Mortgages					1,258,661,000			265,118,000
Unsecured Debt [Member] | Additional Funding Agreement Terms [Member]
Subsequent Event [Line Items]
Line of credit facility, maximum borrowing capacity					3,000,000,000
Unsecured Debt [Member] | Mortgages [Member]
Subsequent Event [Line Items]
Carrying Amount of Mortgages					2,420,000,000
Subsequent Event [Member] | Senior Secured Credit Facility [Member] | Senior Corporate Credit Facility [Member]
Subsequent Event [Line Items]
Line of credit facility, maximum borrowing capacity	6,000,000,000
Line of credit facility, increase (decrease), net	50,000,000
Line of credit facility, current borrowing capacity	4,650,000,000									4,000,000,000	3,600,000,000
Subsequent Event [Member] | Senior Secured Credit Facility [Member] | Senior Corporate Credit Facility [Member] | Swingline Facility [Member]
Subsequent Event [Line Items]
Extinguishment of Debt, Amount		25,000,000
Subsequent Event [Member] | National Institutes Of Health [Member]
Subsequent Event [Line Items]
Face Amount of Mortgages												65,200,000
Real Estate Investment Property, at Cost												40,000,000
Carrying Amount of Mortgages												53,800,000
Default interest rate												5.32%
Subsequent Event [Member] | Multi Tenant Properties [Member]
Subsequent Event [Line Items]
Sale of business, consideration			2,000,000,000
Subsequent Event [Member] | Multi Tenant Properties [Member] | Joint Venture Between Affiliates Of Blackstone Real Estate Partners VII and DDR Corporation [Member]
Subsequent Event [Line Items]
Sale of business, consideration			1,900,000,000
Net proceeds			1,300,000,000
Net proceeds, payment for line of credit			1,200,000,000
Loss on Sale of business			261,100,000
Write off goodwill			195,500,000
Subsequent Event [Member] | Multi Tenant Properties [Member] | Unrelated Third Party Member
Subsequent Event [Line Items]
Sale of business, consideration			$ 52,300,000

[1] For discussion on the restatement adjustments, see Note 2 - Restatement of Previously Issued Financial Statements.