Business Combinations - Schedule of Price Consideration for Business Combination (Detail) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended		12 Months Ended
	Jun. 02, 2011 USD ($)	Jun. 30, 2011 USD ($)	Jun. 30, 2011 EUR (€)	Dec. 31, 2013 AMB [Member] USD ($)	Dec. 31, 2013 PEPR [Member] USD ($)
Business Acquisition [Line Items]
Investments in real estate properties				$ 8,197.6	$ 4,448.2
Investments in and advances to unconsolidated entities				1,592.3
Cash, accounts receivable and other assets				691.3	251.4
Debt				(3,646.7)	(2,240.8)
Accounts payable, accrued expenses and other liabilities				(420.5)	(698.2)
Noncontrolling interests				(557.5)	(133.7)
Total purchase price	$ 5,856.5	$ 1,600.0	€ 1,100.0	$ 5,856.5	$ 1,626.9