Accounts Payable and Accrued Expenses (Detail) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Accounts Payable and Accrued Expenses [Line Items]
Trade payables	$ 16,226,000	$ 12,678,000
Sales commissions payable	5,549,000	4,578,000
Sales tax accrual	3,295,000	0
Accrued payroll and related taxes	3,151,000	1,574,000
Total	$ 28,221,000	$ 18,830,000