Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues:
Revenues	$ 116,628	$ 119,035	$ 233,830	$ 238,915
Expenses:
Rental property operating expenses	40,731	41,501	80,922	83,026
Reimbursed expenses	860	907	1,802	1,772
General and administrative expenses	8,071	8,618	14,880	14,828
Interest expense	9,714	8,523	19,492	18,264
Depreciation and amortization	45,675	50,040	90,768	104,924
Acquisition and transaction costs	137	246	228	2,177
Other	44	236	364	612
Total costs and expenses	105,232	110,071	208,456	225,603
Gain (loss) on extinguishment of debt	0	1,829	(85)	1,829
Income from continuing operations before unconsolidated joint ventures and loss on sale of investment properties	11,396	10,793	25,289	15,141
Income from unconsolidated joint ventures	5,036	40,320	7,921	40,901
Income from continuing operations before gain on sale of investment properties	16,432	51,113	33,210	56,042
Gain on sale of investment properties	5,317	119,832	4,945	119,761
Net income	21,749	170,945	38,155	175,803
Net income attributable to noncontrolling interests	(473)	(2,856)	(836)	(2,963)
Net income available to common stockholders	$ 21,276	$ 168,089	$ 37,319	$ 172,840
Net income per common share — basic and diluted (in usd per share)	$ 0.05	$ 0.40	$ 0.09	$ 0.42
Weighted average shares — basic (in shares)	420,294	419,402	420,225	411,137
Weighted average shares — diluted (in shares)	427,501	427,180	427,444	419,227
Dividends declared per common share (in usd per share)	$ 0.065	$ 0.060	$ 0.130	$ 0.180
Rental property revenues
Revenues:
Revenues	$ 113,698	$ 114,007	$ 227,046	$ 226,524
Fee income
Revenues:
Revenues	1,798	1,854	4,692	3,791
Other
Revenues:
Revenues	$ 1,132	$ 3,174	$ 2,092	$ 8,600