Condensed Consolidating Financial Information - Condensed Consolidated Statements of Cash Flows (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Operating activities
Net cash provided by (used in) operating activities	$ 95,744	$ 101,564
Investing activities
Cash paid for acquisitions and other related investments	(182,982)	(371,500)
Principal received on loans receivable	8,381	4,694
Net proceeds from sale of real estate	34,649	18,409
Investments in loans receivable	(9,102)	(1,445)
Construction in progress and other	(97,002)	(63,422)
Net cash used for investing activities	(246,056)	(413,264)
Financing activities
Revolving credit facilities, net	(105,000)	(80,000)
Additions to term debt	425,000	153,000
Payments of term debt	(100,197)	(11,185)
Distributions paid	(108,026)	(87,928)
Proceeds from sale of common shares/units, net of offering costs	128,270	313,319
Lease deposits and other obligations to tenants	10,879	3,589
Debt issuance costs paid and other financing activities	(11,757)	(4,282)
Net cash provided by financing activities	239,169	286,513
Increase (decrease) in cash and cash equivalents for period	88,857	(25,187)
Effects of exchange rate changes on cash	(2,024)
Cash and cash equivalents at beginning of period	45,979	37,311
Cash and cash equivalents at end of period	132,812	12,124
Eliminations [Member]
Financing activities
Distributions paid	107,842	87,727
Proceeds from sale of common shares/units, net of offering costs	(128,270)	(313,319)
Net payments relating to intercompany financing	20,428	225,592
Parent [Member]
Operating activities
Net cash provided by (used in) operating activities	(98)	91
Financing activities
Distributions paid	(107,842)	(87,727)
Proceeds from sale of common shares/units, net of offering costs	128,270	313,319
Net payments relating to intercompany financing	(20,330)	(225,683)
Net cash provided by financing activities	98	(91)
Subsidiary Issuers [Member]
Operating activities
Net cash provided by (used in) operating activities	(76,425)	(38,891)
Investing activities
Construction in progress and other	(1,030)	(765)
Net cash used for investing activities	(1,030)	(765)
Financing activities
Revolving credit facilities, net	(105,000)	(80,000)
Additions to term debt	425,000
Payments of term debt	(100,176)	(11,000)
Distributions paid	(108,026)	(87,928)
Proceeds from sale of common shares/units, net of offering costs	128,270	313,319
Lease deposits and other obligations to tenants	(360)
Net payments relating to intercompany financing	(61,206)	(267,545)
Debt issuance costs paid and other financing activities	(11,757)	(4,282)
Net cash provided by financing activities	166,745	15,564
Increase (decrease) in cash and cash equivalents for period	89,290
Cash and cash equivalents at beginning of period	18,815	35,483
Cash and cash equivalents at end of period	108,105	11,391
Subsidiary Guarantors [Member]
Operating activities
Net cash provided by (used in) operating activities	221,310	171,742
Investing activities
Cash paid for acquisitions and other related investments	(182,982)	(356,250)
Construction in progress and other	(95,489)	(63,690)
Net cash used for investing activities	(278,471)	(419,940)
Financing activities
Lease deposits and other obligations to tenants	9,431	1,699
Net payments relating to intercompany financing	46,445	244,934
Net cash provided by financing activities	55,877	246,633
Increase (decrease) in cash and cash equivalents for period	(1,284)
Effects of exchange rate changes on cash	(2,024)
Cash and cash equivalents at beginning of period	27,094	1,565
Cash and cash equivalents at end of period	23,786
Non-Guarantor Subsidiaries [Member]
Operating activities
Net cash provided by (used in) operating activities	(49,043)	(31,378)
Investing activities
Cash paid for acquisitions and other related investments		(15,250)
Principal received on loans receivable	8,381	4,694
Net proceeds from sale of real estate	34,649	18,409
Investments in loans receivable	(9,102)	(1,445)
Construction in progress and other	(483)	1,033
Net cash used for investing activities	33,445	(7,441)
Financing activities
Payments of term debt	(21)	(185)
Lease deposits and other obligations to tenants	1,808	1,890
Net payments relating to intercompany financing	14,662	22,702
Net cash provided by financing activities	16,449	24,407
Increase (decrease) in cash and cash equivalents for period	851
Cash and cash equivalents at beginning of period	70	263
Cash and cash equivalents at end of period	$ 921	$ 733