Commitments And Contingencies (Details)	3 Months Ended	9 Months Ended	3 Months Ended		9 Months Ended				9 Months Ended
	Mar. 31, 2013 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2013 Sentrum Portfolio [Member] USD ($)	Mar. 31, 2013 Sentrum Portfolio [Member] USD ($)	Sep. 30, 2013 Sentrum Portfolio [Member] USD ($)	Sep. 30, 2013 Sentrum Portfolio [Member] GBP (£)	Jul. 11, 2012 Sentrum Portfolio [Member] USD ($)	Jul. 11, 2012 Sentrum Portfolio [Member] GBP (£)	Sep. 30, 2013 29 A International Business Park [Member] USD ($)	Sep. 30, 2013 29 A International Business Park [Member] SGD	Sep. 30, 2013 Convergence Business Park [Member] USD ($)
Commitments and Contingencies [Line Items]
Contingent liability			$ 73,100,000		$ 73,100,000	£ 45,200,000	$ 87,600,000	£ 56,500,000
Change in fair value of accrued contingent consideration	(5,800,000)	(13,000)	900,000	5,800,000	13,000
Earnout payment					25,800,000	16,900,000
Additional performance based consideration earned (maximum)										50,000,000
Additional performance based consideration earned (maximum), adjusted for exchange rate									39,800,000
Expiration of earnout contingency									November 2020	November 2020
Lease expiration period											April 2017
Sale price of building											24,000,000
Real estate price, per square acre											225,000
Commitments related to construction contracts		$ 191,700,000