Notes Receivable - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable, net	$ 53,172,000	$ 64,239,000
Chattel Loans receivable	32,700,000	43,400,000
Contract receivables	16,100,000	16,400,000
Receivables, allowances	4,700,000	4,900,000
Fair value of Chattel loans acquired		25,700,000
Certain Loans Acquired in Transfer, Accretable Yield	0.210	0.170
Non Cash Repossession	5,313,000	2,685,000	566,000
Chattel Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, stated interest yield per annum	7.80%
Notes Receivable Yield Rate	18.30%
Loans receivable, amortization term	14 years
Proceeds from receivables repaid	5,500,000	2,600,000
Additional loan to customers	700,000	300,000
Allowance for Loan and Lease Losses, Real Estate	400,000	400,000
Non Cash Repossession	5,300,000	2,700,000
Contract Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables, allowances	700,000	1,000,000
Contract Receivable, weighted average rate	15.90%
Loans receivable, amortization term	4 years
Proceeds from receivables repaid	7,100,000	7,300,000
Additional loan to customers	$ 6,600,000	$ 6,600,000