Notes Receivable - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	$ 18.3	$ 18.9
Contract receivables	$ 18.0	18.2
Chattel Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, stated interest yield per annum	7.80%
Notes receivable yield rate	21.70%
Weighted average remaining amortization period	11 years
Notes receivable, allowance	$ 0.3	0.4
Contract Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted average remaining amortization period	4 years
Provision for uncollectible receivable	$ 0.6	$ 0.6
Contracts Receivable, yield interest at a stated per annum average	16.10%