Receivables - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Receivables, Net [Line Items]
Interest-bearing financing fee receivables	$ 69,464	$ 76,481
Allowance for doubtful accounts receivables	28,777	23,017	19,450	15,017
Aggregate carrying amount of non-interest bearing receivables	443,211	401,562
Financing Receivables [Member]
Receivables, Net [Line Items]
Allowance for doubtful accounts receivables	0	0
Trade Receivables [Member]
Receivables, Net [Line Items]
Receivables past due or deemed uncollectible	$ 39,341	$ 25,604