CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) shares in Thousands, $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 98,409	$ 114,425
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	214,938	186,234
Amortization of deferred financing fees and debt discounts and premiums	4,272	4,541
Straight line rental income	(13,598)	(13,739)
Amortization of acquired real estate leases and other intangible assets	(3,795)	(3,461)
Loss on early extinguishment of debt	90	1,469
Impairment of assets	16,930	504
Gain on sale of properties	(4,061)	0
Gain on sale of investments	0	(71)
Other non-cash adjustments	(2,828)	(1,714)
Equity in earnings of an investee	(107)	(70)
Change in assets and liabilities:
Restricted cash	(170)	2,365
Other assets	2,990	(9,561)
Accrued interest	16,156	13,616
Other liabilities	13,170	26,303
Cash provided by operating activities	342,396	320,841
Cash flows from investing activities:
Real estate acquisitions and deposits	(188,523)	(1,132,760)
Real estate improvements	(72,455)	(55,983)
Investment in The RMR Group Inc.	0	(16,588)
Proceeds from sale of properties	29,179	2,755
Proceeds from sale of investments	0	6,571
Cash used for investing activities	(231,799)	(1,196,005)
Cash flows from financing activities:
Proceeds from issuance of common shares, net	0	659,496
Proceeds from issuance of senior unsecured notes	250,000	0
Proceeds from unsecured term loans	0	200,000
Proceeds from borrowings on revolving credit facility	505,000	1,308,000
Proceeds from issuance of secured debt	620,000	0
Repayments of borrowings on revolving credit facility	(1,065,000)	(920,243)
Repayment of other debt	(127,202)	(70,087)
Loss on early extinguishment of debt settled in cash	0	(1,448)
Payment of debt issuance costs	(12,016)	(2,758)
Repurchase of common shares	(416)	(212)
Distributions to shareholders	(277,846)	(263,770)
Cash (used for) provided by financing activities	(107,480)	908,978
Increase in cash and cash equivalents	3,117	33,814
Cash and cash equivalents at beginning of period	37,656	27,594
Cash and cash equivalents at end of period	40,773	61,408
Supplemental cash flows information:
Interest paid	103,409	94,681
Income taxes paid	$ 363	$ 477
Non-cash investing activities:
Investment funded by issuance of common shares (in shares)	0	(44,461)
Acquisitions funded by assumed debt	$ 0	$ (181,432)
Non-cash financing activities:
Assumption of mortgage notes payable	0	181,432
Issuance of common shares	$ 0	$ 47,691