Schedule III - Real Estate and Accumulated Depreciation (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Real estate
Rollforward of Carrying Amounts of Real Estate Investments
Beginning balance	$ 2,396,715	$ 2,402,315	$ 2,107,549
Additions	222,739	65,115	226,123
Improvements	9,450	3,554	8,970
Dispositions	0	(32,739)	0
Foreign currency translation adjustment	(99,252)	(124,536)	30,155
Reclassification from real estate under construction	129,225	83,006	29,518
Ending balance	2,658,877	2,396,715	2,402,315
Rollforward of Accumulated Depreciation of Real Estate Investments
Beginning balance	175,478	129,051	77,326
Depreciation expense	57,831	54,976	49,785
Foreign currency translation adjustment	(7,442)	(8,549)	1,940
Ending balance	225,867	175,478	129,051
Operating Real Estate – Self-Storage Facilities
Rollforward of Carrying Amounts of Real Estate Investments
Beginning balance	272,859	283,370	254,805
Additions	0	0	27,697
Improvements	2,662	2,047	1,369
Dispositions	0	(27,487)	(13,058)
Reclassification from real estate under construction	0	14,929	12,557
Ending balance	275,521	272,859	283,370
Rollforward of Accumulated Depreciation of Real Estate Investments
Beginning balance	22,217	15,354	7,757
Depreciation expense	8,091	8,664	8,470
Dispositions	0	(1,801)	(873)
Ending balance	$ 30,308	$ 22,217	$ 15,354