Significant Accounting Policies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Significant Accounting Policies [Line Items]
Foreign currency remeasurement gains (losses), net	$ (761)	$ 1,406	$ (1,606)
Depreciation and amortization expense	30,855	24,580	22,712
Collateralized borrowing activities	13,854	8,928
Reimbursements of expenses	$ 24,762	$ 18,942	$ 20,216