Income Taxes - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Mar. 31, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Income tax expense	$ 4,230	$ 4,329		$ 10,842	$ 10,975
Effective tax rates	24.20%	27.00%		25.20%	27.00%
Income tax holiday on the Phillipines operations				May 2012
Company's current benefits from income tax holiday				4 years
Extendable income tax holiday				4 years
Number of year of expected extendable period				1 year
Number of year of extended retroactive				1 year
Tax benefit expiration date				May 2014
Tax exemption on profit of the Company's Bengaluru operations			100.00%	50.00%
Period completed by Bengaluru operation				5 years
Valuation allowance	665			665		665
Deferred income taxes related to the MAT	2,989			2,989		2,932
Deferred income taxes related to the MAT expiration year				2024
Recognized interest and penalties	52			169
Unrecognized tax benefits	$ 2,774			$ 2,774		$ 3,019