CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net income	$ 40,833	$ 65,603
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation	76,798	68,607
Amortization of deferred financing fees and debt discounts	2,068	3,024
Straight line rental income	(3,698)	(6,062)
Amortization of acquired real estate leases and other intangible assets	1,935	(170)
Loss on early extinguishment of debt	105
Impairment of assets	33,571	3,071
Equity in earnings of an investee	(155)	(121)
Change in assets and liabilities:
Restricted cash	(2,973)	(2,916)
Other assets	1,135	10,719
Accrued interest	(63)	(8,966)
Other liabilities	1,376	13,740
Cash provided by operating activities	150,932	146,529
Cash flows from investing activities:
Real estate acquisitions and deposits	(76,006)	(123,867)
Real estate improvements	(22,669)	(20,015)
Principal payments on loan receivable		38,000
Cash used for investing activities	(98,675)	(105,882)
Cash flows from financing activities:
Proceeds from issuance of common shares, net	261,813
Proceeds from borrowings on revolving credit facility	45,000	434,000
Repayments of borrowings on revolving credit facility	(205,000)	(74,000)
Redemption of senior notes		(225,000)
Repayment of other debt	(16,662)	(54,889)
Payment of deferred financing fees	(248)	(294)
Distributions to shareholders	(142,206)	(123,619)
Cash used for financing activities	(57,303)	(43,802)
Decrease in cash and cash equivalents	(5,046)	(3,155)
Cash and cash equivalents at beginning of period	42,382	23,560
Cash and cash equivalents at end of period	37,336	20,405
Supplemental cash flow information:
Interest paid	57,126	62,951
Income taxes paid	516	378
Non-cash investing activities:
Acquisitions funded by assumed debt	(12,266)	(56,789)
Non-cash financing activities:
Assumption of mortgage notes payable	12,266	56,789
Issuance of common shares	$ 929	$ 657