Estimated Fair Value of Assets Acquired and Liabilities Assumed in Acquisition Determined using Level Two and Level Three Inputs (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012
Assets acquired
Property, plant And equipment	$ 1,431,000
Notes receivable	40,000
Other assets	12,000
Total Assets acquired	1,483,000
Liabilities assumed
Mortgage notes payable	548,000
Accrued payroll and other operating expenses	3,000
Rents and other customer payments received in advance and security deposits	5,000
Total Liabilities assumed	556,000
Net consideration paid	927,000
Land
Assets acquired
Property, plant And equipment	474,000
Depreciable property
Assets acquired
Property, plant And equipment	859,000
Manufactured homes
Assets acquired
Property, plant And equipment	24,000
In-place leases
Assets acquired
Property, plant And equipment	$ 74,000