CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Cash Flows [Abstract]
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 32,281	$ 31,272
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	73,175	71,223
Amortization of debt issuance costs and debt discounts and premiums	1,459	1,356
Straight line rental income	(3,429)	(4,561)
Amortization of acquired real estate leases and other intangible assets	(1,291)	(1,254)
Loss on early extinguishment of debt	0	6
Impairment of assets	0	7,390
Other non-cash adjustments	(943)	(985)
Equity in earnings of an investee	(128)	(77)
Change in assets and liabilities:
Restricted cash	703	(698)
Other assets	3,901	664
Accrued interest	15,051	16,654
Other liabilities	(6,001)	1,821
Net cash provided by operating activities	114,778	122,811
Cash flows from investing activities:
Real estate acquisitions and deposits	(14,326)	(23,651)
Real estate improvements	30,171	23,173
Proceeds from sale of properties	0	644
Net cash used for investing activities	(44,497)	(46,180)
Cash flows from financing activities:
Proceeds from issuance of senior unsecured notes	0	250,000
Proceeds from borrowings on revolving credit facility	94,000	98,000
Repayments of borrowings on revolving credit facility	(324,000)	(312,000)
Repayment of other debt	(2,929)	(9,957)
Payment of debt issuance costs	0	(8,517)
Proceeds from noncontrolling interest, net	255,813	0
Distributions to shareholders	(92,642)	(92,614)
Net cash used for financing activities	(69,758)	(75,088)
Increase in cash and cash equivalents	523	1,543
Cash and cash equivalents at beginning of period	31,749	37,656
Cash and cash equivalents at end of period	32,272	39,199
Supplemental cash flows information:
Interest paid	$ 26,978	$ 21,269