Reportable Segments Reportable Segments - Income from Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues:
Community base rental income									$ 442,046	$ 426,886	$ 409,801
Resort base rental income									184,760	163,968	147,234
Right-to-use annual payments									44,443	44,860	47,967
Right-to-use contracts current period, gross									12,783	13,892	13,815
Right-to-use contract upfront payments, deferred, net									(4,231)	(5,501)	(5,694)
Utility and other income									76,153	70,209	63,800
Gross revenue from home sales									33,150	28,418	17,871
Brokered resale revenues and ancillary services revenues, net									4,149	3,850	4,212
Rental home income									14,012	14,827	14,267
Total revenues	$ 201,616	$ 210,144	$ 201,480	$ 208,414	$ 190,261	$ 200,778	$ 189,025	$ 196,745	821,654	776,809	729,048
Expenses:
Property operating and maintenance									254,668	243,914	229,897
Real estate taxes									50,962	48,714	48,279
Sales and marketing, gross									11,751	12,418	13,509
Right-to-use contract commissions, deferred, net									(1,556)	(2,617)	(2,410)
Property management									44,528	42,638	40,193
Cost of home sales									32,279	26,747	17,296
Home selling expenses									3,191	2,342	2,085
Rental home operating and maintenance									7,167	7,441	7,474
Total property operations expenses									675,231	644,376	653,840
Income from property operations segment									146,423	132,433	75,208
Property Operations Segment
Revenues:
Community base rental income									442,046	426,886	409,801
Resort base rental income									184,760	163,968	147,234
Right-to-use annual payments									44,443	44,860	47,967
Right-to-use contracts current period, gross									12,783	13,892	13,815
Right-to-use contract upfront payments, deferred, net									(4,231)	(5,501)	(5,694)
Utility and other income									76,153	70,209	63,800
Ancillary services revenues, net									2,880	2,628	3,069
Total revenues									758,834	716,942	679,992
Expenses:
Property operating and maintenance									254,668	243,914	229,897
Real estate taxes									50,962	48,714	48,279
Sales and marketing, gross									11,751	12,418	13,509
Right-to-use contract commissions, deferred, net									(1,556)	(2,617)	(2,410)
Property management									44,528	42,638	40,193
Total property operations expenses									360,353	345,067	329,468
Income from property operations segment									398,481	371,875	350,524
Home Sales And Rentals
Revenues:
Gross revenue from home sales									33,150	28,418	17,871
Brokered resale revenues and ancillary services revenues, net									1,269	1,222	1,143
Rental home income									14,012	14,827	14,267
Total revenues									48,431	44,467	33,281
Expenses:
Cost of home sales									32,279	26,747	17,296
Home selling expenses									3,191	2,342	2,085
Rental home operating and maintenance									7,167	7,441	7,474
Total property operations expenses									42,637	36,530	26,855
Income from property operations segment									$ 5,794	$ 7,937	$ 6,426