Investments in Unconsolidated Joint Ventures (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2011 Property Location		Sep. 30, 2010	Sep. 30, 2011 MortgageLoan Property Location		Sep. 30, 2010	Dec. 31, 2010
Schedule of Equity Method Investments [Line Items]
Number of Sites	3,075			3,075
Investment in joint ventures	$ 8,238			$ 8,238			$ 8,446
Equity in income of unconsolidated joint ventures	257		314	1,582		1,714
Meadows Investments | Various
Schedule of Equity Method Investments [Line Items]
Number of Sites	1,027			1,027
Economic Interest	50.00%	[1]		50.00%	[1]
Investment in joint ventures	433			433			276
Equity in income of unconsolidated joint ventures				685		823
Lakeshore Investments | Florida
Schedule of Equity Method Investments [Line Items]
Number of Sites	342			342
Economic Interest	65.00%	[1]		65.00%	[1]
Investment in joint ventures	139			139			115
Equity in income of unconsolidated joint ventures				196		174
Voyager | Arizona
Schedule of Equity Method Investments [Line Items]
Number of Sites	1,706			1,706
Economic Interest	50.00%	[1],[2]		50.00%	[1],[2]
Investment in joint ventures	7,666			7,666			8,055
Equity in income of unconsolidated joint ventures				$ 701		$ 717

[1] The percentages shown approximate the Company's economic interest as of September 30, 2011. The Company's legal ownership interest may differ.

[2] Voyager joint venture primarily consists of a 50% interest in Voyager RV Resort and a 25% interest in the utility plant servicing the Property.