Revenues and NOI for Reportable Segment (Detail) - Parent Company [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Information
Total operating revenues	$ 382,791	$ 272,236	$ 761,699	$ 541,252
Net Operating Income	236,822	169,281	474,457	337,416
Depreciation and amortization	(126,360)	(75,742)	(256,357)	(150,870)
Acquisition expense	0	(421)	0	(1,134)
Property management expense	(10,745)	(8,310)	(21,726)	(17,313)
General and administrative expense	(9,534)	(7,014)	(22,374)	(13,596)
Merger related expenses	(978)	0	(3,849)	0
Business Combination, Integration Related Costs	(3,229)	0	(6,519)	0
Interest and other non-property (expense) income	650	62	3,329	94
Interest expense	(38,481)	(32,039)	(75,065)	(64,250)
Loss on debt extinguishment	2,217	0	2,340	3
Gain on sale of depreciable real estate assets excluded from discontinued operations	274	68	201	823
Net casualty loss after insurance and other settlement proceeds	(240)	1,760	(331)	813
Income tax expense	(618)	(457)	(1,269)	(745)
Gain on sale of non-depreciable real estate assets	48	543	48	2,170
Gain (loss) from real estate joint ventures	329	(101)	686	27
Net income attributable to noncontrolling interests	(1,840)	(2,486)	(3,351)	(4,881)
Preferred Stock Dividends, Income Statement Impact	(922)	0	(1,844)	0
Net Income (Loss) Available to Common Stockholders, Basic	47,393	45,144	88,376	88,557
Large Market Same Store
Segment Information
Total property revenues	167,712	162,487	333,971	322,679
Net Operating Income	104,098	101,108	208,845	200,635
Secondary Market Same Store
Segment Information
Total property revenues	87,231	84,770	173,377	168,863
Net Operating Income	54,544	52,745	108,781	106,139
Non-Same Store and Other
Segment Information
Total property revenues	127,848	24,979	254,351	49,710
Net Operating Income	$ 78,180	$ 15,428	$ 156,831	$ 30,642