CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 685,108	$ 582,585
Accounts receivable, net of allowance of $3,039 and $1,186, respectively	282,276	265,639
Unbilled revenues	129,683	86,500
Prepaid and other current assets, net of allowance of $50 and $45, respectively	29,646	23,196
Employee loans, current, net of allowance of $23 and $0, respectively	2,289	2,113
Total current assets	1,129,002	960,033
Property and equipment, net	99,465	86,419
Employee loans, noncurrent, net of allowance of $0 and $0, respectively	1,456	2,097
Intangible assets, net	52,669	44,511
Goodwill	144,987	119,531
Deferred tax assets	61,905	24,974
Other noncurrent assets, net of allowance of $0 and $140, respectively	14,498	12,691
Total assets	1,503,982	1,250,256
Current liabilities
Accounts payable	8,422	5,574
Accrued expenses and other current liabilities	98,442	89,812
Due to employees	52,405	38,757
Deferred compensation due to employees	9,174	5,964
Taxes payable	52,530	40,860
Total current liabilities	220,973	180,967
Long-term debt	25,028	25,033
Taxes payable, noncurrent	50,242	59,874
Other noncurrent liabilities	11,804	9,435
Total liabilities	308,047	275,309
Commitments and contingencies (Note 11)
Stockholders’ equity
Common stock, $0.001 par value; 160,000,000 authorized; 54,011,579 and 53,003,420 shares issued, 53,991,844 and 52,983,685 shares outstanding at September 30, 2018 and December 31, 2017, respectively	54	53
Additional paid-in capital	530,837	473,874
Retained earnings	699,568	518,820
Treasury stock	(177)	(177)
Accumulated other comprehensive loss	(34,347)	(17,623)
Total stockholders’ equity	1,195,935	974,947
Total liabilities and stockholders’ equity	$ 1,503,982	$ 1,250,256