Notes Receivable - Additional Information (Detail) (USD $)	9 Months Ended			9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Sep. 30, 2012 Contract Receivable	Dec. 31, 2011 Contract Receivable	Sep. 30, 2012 Chattel Loans	Dec. 31, 2011 Chattel Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable, net	$ 56,056,000		$ 64,239,000
Chattel Loans receivable	35,668,000		43,434,000
Home loans repossessed	3,506,000	361,000				3,506,000	2,685,000
Loans receivable, stated interest yield per annum						7.80%
Loans receivable, amortization term				4 years		14 years
Notes receivable, allowance						415,000	415,000
Proceeds from receivables repaid				5,410,000	7,273,000	4,168,000	2,612,000
Additional loan to customers				4,735,000	6,633,000	491,000	315,700
Contract receivables	16,034,000		16,440,000
Provision for uncollectible receivable	$ 4,900,000		$ 4,400,000	$ 778,000	$ 974,000
Contracts Receivable, yield interest at a stated per annum average				16.00%