Employee Benefit Plans - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Employee contribution percentage	60.00%
Employee contribution amount	$ 17,000
Provident Fund
Defined Benefit Plan Disclosure [Line Items]
Contribution expense recognized by Indian entities	900,000	900,000
Gratuity Plan
Defined Benefit Plan Disclosure [Line Items]
Contribution expense recognized by Indian entities	800,000	600,000
Accrued liability for retirement plan	$ 8,800,000		$ 8,200,000