CONDENSED CONSOLIDATED BALANCE SHEETS - UNAUDITED - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 119,671	$ 122,243
Short-term investments	66,693	139,117
Total cash, cash equivalents and short-term investments	186,364	261,360
Trade accounts receivable:
Billed, net of allowance of $3,961 and $4,149	239,913	219,531
Unbilled	38,832	31,187
Income taxes receivable	10,951	13,839
Other current assets	38,185	28,349
Total current assets	514,245	554,266
Non-current assets:
Property and equipment, net of depreciation of $108,542 and $123,126	75,040	44,651
Intangible assets	72,499
Goodwill	210,605	210,080
Client contract costs, net of amortization of $30,932 and zero	35,527
Deferred income taxes	12,303	14,057
Other assets	7,012	10,948
Total non-current assets	412,986	350,268
Total assets	927,231	904,534
Current liabilities:
Current portion of long-term debt	7,500	22,500
Client deposits	35,626	31,053
Trade accounts payable	37,316	38,420
Accrued employee compensation	44,498	62,984
Deferred revenue	39,558	41,885
Income taxes payable	1,006	1,216
Other current liabilities	26,262	24,535
Total current liabilities	191,766	222,593
Non-current liabilities:
Long-term debt, net of unamortized discounts of $16,721 and $18,264	353,904	309,236
Deferred revenue	9,074	12,346
Income taxes payable	2,396	2,415
Deferred income taxes	9,162	4,584
Other non-current liabilities	11,069	10,614
Total non-current liabilities	385,605	339,195
Total liabilities	577,371	561,788
Stockholders' equity:
Preferred stock, par value $.01 per share; 10,000 shares authorized; zero shares issued and outstanding
Common stock, par value $.01 per share; 100,000 shares authorized; 33,561 and 33,516 shares outstanding	692	689
Common stock warrants; 439 warrants vested and 1,425 issued	9,082	9,082
Additional paid-in capital	431,450	427,091
Treasury stock, at cost; 34,334 and 34,075 shares	(826,066)	(814,732)
Accumulated other comprehensive income (loss):
Unrealized loss on short-term investments, net of tax	(114)	(88)
Cumulative foreign currency translation adjustments	(37,255)	(28,734)
Accumulated earnings	772,071	749,438
Total stockholders' equity	349,860	342,746
Total liabilities and stockholders' equity	927,231	904,534
Software
Non-current assets:
Intangible assets	30,926	26,906
Client contracts
Non-current assets:
Intangible assets		$ 43,626
Acquired client contracts
Non-current assets:
Intangible assets	$ 41,573