CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 192,363	$ 220,534	$ 169,207
Time deposits	30,000	0
Accounts receivable, net of allowance of $2,618 and $2,181, respectively	104,714	124,483
Unbilled revenues	88,033	55,851
Prepaid and other current assets	14,390	9,289
Employee loans, net of allowance of $0 and $0, respectively, current	2,498	2,434
Deferred tax assets, current	1,817	2,496
Total current assets	433,815	415,087
Property and equipment, net	55,115	55,134
Restricted cash, long-term	114	156
Employee loans, net of allowance of $0 and $0, respectively, long-term	3,806	4,081
Intangible assets, net	45,091	47,689
Goodwill	56,346	57,417
Deferred tax assets, long-term	11,453	11,094
Other long-term assets	3,794	3,368
Total assets	609,534	594,026
Current liabilities
Accounts payable	13,366	4,641
Accrued expenses and other liabilities	20,579	32,203
Deferred revenue, current	3,061	3,220
Due to employees	29,870	24,518
Taxes payable	16,005	24,704
Contingent consideration, current (Note 2 and 4)	33,919	35,524
Contingent liability, current (Note 9)	92	0
Deferred tax liabilities, current	705	603
Total current liabilities	117,597	125,413
Deferred tax liabilities, long-term	4,106	4,563
Total liabilities	121,703	129,976
Commitments and contingencies (Note 9)
Stockholders’ equity
Common stock, $0.001 par value; 160,000,000 authorized; 49,111,297 and 48,748,298 shares issued, 48,692,313 and 48,303,811 shares outstanding at March 31, 2015 and December 31, 2014, respectively	48	48
Additional paid-in capital	241,066	229,501
Retained earnings	275,312	260,598
Treasury stock	(3,811)	(4,043)
Accumulated other comprehensive loss	(24,784)	(22,054)
Total stockholders’ equity	487,831	464,050
Total liabilities and stockholders’ equity	$ 609,534	$ 594,026