CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 584,081	$ 582,585
Accounts receivable, net of allowance of $2,790 and $1,186, respectively	283,001	265,639
Unbilled revenues	123,434	86,500
Prepaid and other current assets, net of allowance of $42 and $45, respectively	31,919	23,196
Employee loans, current, net of allowance of $0 and $0, respectively	2,084	2,113
Total current assets	1,024,519	960,033
Property and equipment, net	98,450	86,419
Employee loans, noncurrent, net of allowance of $0 and $0, respectively	1,669	2,097
Intangible assets, net	55,201	44,511
Goodwill	144,667	119,531
Deferred tax assets	54,805	24,974
Other noncurrent assets, net of allowance of $130 and $140, respectively	12,884	12,691
Total assets	1,392,195	1,250,256
Current liabilities
Accounts payable	6,727	5,574
Accrued expenses and other current liabilities	72,443	89,812
Due to employees	50,374	38,757
Deferred compensation due to employees	4,338	5,964
Taxes payable	47,529	40,860
Total current liabilities	181,411	180,967
Long-term debt	25,020	25,033
Taxes payable, noncurrent	56,540	59,874
Other noncurrent liabilities	16,421	9,435
Total liabilities	279,392	275,309
Commitments and contingencies (Note 11)
Stockholders’ equity
Common stock, $0.001 par value; 160,000,000 authorized; 53,705,002 and 53,003,420 shares issued, 53,685,267 and 52,983,685 shares outstanding at June 30, 2018 and December 31, 2017, respectively	54	53
Additional paid-in capital	511,131	473,874
Retained earnings	633,950	518,820
Treasury stock	(177)	(177)
Accumulated other comprehensive loss	(32,155)	(17,623)
Total stockholders’ equity	1,112,803	974,947
Total liabilities and stockholders’ equity	$ 1,392,195	$ 1,250,256

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.