Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 151,319	$ 176,499
Short-term investments	14,330	11,577
Restricted cash	2,774	1,395
Accounts receivable, net	89,323	80,244
Prepaid expenses	9,875	5,783
Deferred tax assets, net	4,921	4,455
Advance income tax, net	9,305	9,905
Other current assets	13,241	12,533
Total current assets	295,088	302,391
Fixed assets, net	47,467	45,369
Restricted cash	3,367	3,258
Deferred tax assets, net	8,288	11,985
Intangible assets, net	60,085	46,979
Goodwill	172,097	139,599
Other assets	24,626	23,975
Total assets	611,018	573,556
Current liabilities:
Accounts payable	5,510	4,663
Short-term borrowings	5,000
Deferred revenue	13,246	7,690
Accrued employee cost	21,021	37,606
Accrued expenses and other current liabilities	39,386	40,206
Current portion of capital lease obligations	743	803
Total current liabilities	84,906	90,968
Long term borrowings	75,000	50,000
Capital lease obligations, less current portion	424	560
Non-current liabilities	13,727	12,870
Total liabilities	174,057	154,398
Commitments and contingencies (See Note 16)
Preferred stock, $0.001 par value; 15,000,000 shares authorized, none issued
Stockholders' equity:
Common stock, $0.001 par value; 100,000,000 shares authorized, 34,605,579 shares issued and 33,294,828 shares outstanding as of March 31, 2015 and 34,203,352 shares issued and 32,905,467 shares outstanding as of December 31, 2014	35	34
Additional paid-in-capital	239,311	233,173
Retained earnings	278,991	269,424
Accumulated other comprehensive loss	(53,015)	(55,509)
Total stockholders' equity including shares held in treasury	465,322	447,122
Less: 1,310,751 shares as of March 31, 2015 and 1,297,885 shares as of December 31, 2014, held in treasury, at cost	(28,361)	(27,964)
Total stockholders' equity	436,961	419,158
Total liabilities and stockholders' equity	$ 611,018	$ 573,556