Real Estate (Details Textual) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2012 sqft acre Property	Jun. 30, 2011	Jun. 30, 2012 Buildings sqft acre Property	Jun. 30, 2011	Dec. 31, 2011 sqft Property acre
Business Acquisition [Line Items]
Number of real estate properties	1,927		1,927		1,797
Net investments in properties	$ 24,166,196,000		$ 24,166,196,000		$ 22,629,630,000
Real Estate (Textual) [Abstract]
Square footage of industrial property			328,000,000		291,100,000
Total expected investment upon completion of the properties under development	1,000,000,000		1,000,000,000
Acreage of land held for development	10,508		10,508		10,723
Acquisition acres of land	167		167
Total purchase amount of land			74,823,000	64,749,000
Gains on acquisitions and dispositions of investments in real estate, net	520,000	102,529,000	268,291,000	106,254,000
Number of operating buildings acquired			8
Square feet of operating buildings	900,000		900,000
Payments to Acquire Buildings			42,500,000
Square feet of properties	100,000		100,000
Impairment of other assets		(103,823,000)	(16,135,000)	(103,823,000)
Pre-Stabilized Completed Properties [Member]
Business Acquisition [Line Items]
Number of properties under development	29		29		30
Development Portfolio [Member]
Business Acquisition [Line Items]
Square footage of under developed property	10,600,000		10,600,000		9,500,000
Prologis California [Member]
Real Estate (Textual) [Abstract]
Gains on acquisitions and dispositions of investments in real estate, net			273,000,000
Quarter One Venture Acquisition [Member]
Business Acquisition [Line Items]
Number of real estate properties	180		180
Net investments in properties	$ 2,100,000,000		$ 2,100,000,000