Reportable Segments - Consolidated Net Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Depreciation on real estate assets and rental homes	$ (32,856)	$ (30,493)	$ (96,630)	$ (90,849)
Amortization of in-place leases	(2,124)	(138)	(5,069)	(2,128)
Reconciliation to Consolidated net income:
Income from other investments, net	5,421	2,052	9,774	3,918
General and administrative	(8,816)	(7,505)	(26,523)	(23,339)
Other expenses	(386)	(324)	(1,096)	(814)
Interest and related amortization	(26,490)	(25,027)	(78,478)	(74,728)
Equity in income of unconsolidated joint ventures	788	686	3,596	2,876
Consolidated net income	59,660	54,865	173,006	162,403
Total assets	3,855,037	3,525,847	3,855,037	3,525,847	$ 3,610,032
Capital improvements	47,061	34,412	128,436	87,877
Property Operations
Reconciliation to Consolidated net income:
Total assets	3,630,136	3,298,122	3,630,136	3,298,122
Capital improvements	21,722	20,308	69,591	52,040
Home Sales and Rentals Operations
Reconciliation to Consolidated net income:
Total assets	224,901	227,725	224,901	227,725
Capital improvements	25,339	14,104	58,845	35,837
Operating Segments
Segment Reporting Information [Line Items]
Operations revenues	249,408	237,599	727,770	685,866
Operations expenses	(127,131)	(123,959)	(365,996)	(343,941)
Income from segment operations	122,277	113,640	361,774	341,925
Interest income	1,841	1,815	5,412	5,378
Depreciation on real estate assets and rental homes	(32,856)	(30,493)	(96,630)	(90,849)
Amortization of in-place leases	(2,124)	(138)	(5,069)	(2,128)
Income (loss) from operations	89,138	84,824	265,487	254,326
Operating Segments | Property Operations
Segment Reporting Information [Line Items]
Operations revenues	236,204	223,184	689,387	648,766
Operations expenses	(114,384)	(110,431)	(329,942)	(310,337)
Income from segment operations	121,820	112,753	359,445	338,429
Interest income	863	773	2,494	2,256
Depreciation on real estate assets and rental homes	(30,425)	(27,879)	(89,308)	(82,939)
Amortization of in-place leases	(2,124)	(138)	(5,069)	(2,128)
Income (loss) from operations	90,134	85,509	267,562	255,618
Operating Segments | Home Sales and Rentals Operations
Segment Reporting Information [Line Items]
Operations revenues	13,204	14,415	38,383	37,100
Operations expenses	(12,747)	(13,528)	(36,054)	(33,604)
Income from segment operations	457	887	2,329	3,496
Interest income	978	1,042	2,918	3,122
Depreciation on real estate assets and rental homes	(2,431)	(2,614)	(7,322)	(7,910)
Amortization of in-place leases	0	0	0	0
Income (loss) from operations	(996)	(685)	(2,075)	(1,292)
Segment Reconciling Items
Reconciliation to Consolidated net income:
Corporate interest income	5	159	246	164
Income from other investments, net	5,421	2,052	9,774	3,918
General and administrative	(8,816)	(7,505)	(26,523)	(23,339)
Other expenses	(386)	(324)	(1,096)	(814)
Interest and related amortization	(26,490)	(25,027)	(78,478)	(74,728)
Equity in income of unconsolidated joint ventures	$ 788	$ 686	$ 3,596	$ 2,876