Reportable Segments - Consolidated Net Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Depreciation and amortization	$ (37,032)	$ (34,980)	$ (112,785)	$ (101,699)
Gain on sale of real estate, net	0	0	52,507	0
Reconciliation to Consolidated net income:
Income from other investments, net	11,263	13,419	31,898	38,991
General and administrative	(8,710)	(8,816)	(27,844)	(26,523)
Other expenses	(1,460)	(386)	(2,427)	(1,096)
Interest and related amortization	(25,547)	(26,490)	(77,964)	(78,478)
Equity in income of unconsolidated joint ventures	3,518	788	8,277	3,596
Early debt retirement	0	0	(1,491)	0
Consolidated net income	68,176	59,660	237,796	173,006
Total assets	4,137,471	3,855,037	4,137,471	3,855,037	$ 3,925,808
Capital improvements	68,344	47,061	189,788	128,436
Property Operations
Reconciliation to Consolidated net income:
Total assets	3,871,379	3,630,136	3,871,379	3,630,136
Capital improvements	26,000	21,722	78,907	69,591
Home Sales and Rentals Operations
Reconciliation to Consolidated net income:
Total assets	266,092	224,901	266,092	224,901
Capital improvements	42,344	25,339	110,881	58,845
Operating Segments
Segment Reporting Information [Line Items]
Operations revenues	262,300	249,408	764,337	727,770
Operations expenses	(133,753)	(127,131)	(379,093)	(365,996)
Income from segment operations	128,547	122,277	385,244	361,774
Interest income	1,825	1,841	5,364	5,412
Depreciation and amortization	(37,032)	(34,980)	(112,785)	(101,699)
Gain on sale of real estate, net			52,507
Income (loss) from operations	93,340	89,138	330,330	265,487
Operating Segments | Property Operations
Segment Reporting Information [Line Items]
Operations revenues	249,632	236,204	729,496	689,387
Operations expenses	(122,683)	(114,384)	(348,546)	(329,942)
Income from segment operations	126,949	121,820	380,950	359,445
Interest income	985	863	2,829	2,494
Depreciation and amortization	(34,273)	(32,549)	(105,013)	(94,377)
Gain on sale of real estate, net			52,507
Income (loss) from operations	93,661	90,134	331,273	267,562
Operating Segments | Home Sales and Rentals Operations
Segment Reporting Information [Line Items]
Operations revenues	12,668	13,204	34,841	38,383
Operations expenses	(11,070)	(12,747)	(30,547)	(36,054)
Income from segment operations	1,598	457	4,294	2,329
Interest income	840	978	2,535	2,918
Depreciation and amortization	(2,759)	(2,431)	(7,772)	(7,322)
Gain on sale of real estate, net			0
Income (loss) from operations	(321)	(996)	(943)	(2,075)
Segment Reconciling Items
Reconciliation to Consolidated net income:
Corporate interest income	6	5	21	246
Income from other investments, net	7,029	5,421	8,894	9,774
General and administrative	(8,710)	(8,816)	(27,844)	(26,523)
Other expenses	(1,460)	(386)	(2,427)	(1,096)
Interest and related amortization	(25,547)	(26,490)	(77,964)	(78,478)
Equity in income of unconsolidated joint ventures	$ 3,518	$ 788	8,277	$ 3,596
Early debt retirement			$ (1,491)