Contributions by the Sponsor (Details) (USD $)	6 Months Ended		0 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Feb. 28, 2013 Sponsor	Feb. 28, 2013 Sponsor Class B Common Shares	Feb. 28, 2013 Sponsor Operating Partnership property	Feb. 28, 2013 Operating Partnership Sponsor Series C Convertible Units
Significant Acquisitions and Disposals
Number of properties					2,770
Total consideration amount			$ 491,700,000
Units issue to Sponsor (in shares)						31,085,974
Common shares issue to Sponsor				634,408
Common shares issue to Sponsor per share				$ 15.50
Common units issue to Sponsor per unit						$ 15.50
Net book value reclassified from additional paid-in capital		30,510,000			386,500,000
Units issue to Sponsor, value						378,800,000
Units issue to Sponsor, value	$ 112,000			$ 7,700,000