CONDENSED CONSOLIDATED BALANCE SHEETS - UNAUDITED - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 125,111	$ 126,351
Short-term investments	119,843	150,147
Total cash, cash equivalents and short-term investments	244,954	276,498
Trade accounts receivable:
Billed, net of allowance of $2,706 and $3,080	197,486	208,930
Unbilled	37,353	30,828
Income taxes receivable	13,517	11,931
Other current assets	37,633	31,751
Total current assets	530,943	559,938
Non-current assets:
Property and equipment, net of depreciation of $129,475 and $122,866	36,343	33,116
Intangible assets	66,979	71,102
Goodwill	206,634	201,094
Deferred income taxes	13,455	14,218
Other assets	10,040	12,411
Total non-current assets	333,451	331,941
Total assets	864,394	891,879
Current liabilities:
Current portion of long-term debt, net of unamortized discounts of zero and $296	18,750	49,426
Client deposits	32,590	33,916
Trade accounts payable	29,982	35,118
Accrued employee compensation	50,314	65,341
Deferred revenue	57,865	45,064
Income taxes payable	423	822
Other current liabilities	18,960	22,342
Total current liabilities	208,884	252,029
Non-current liabilities:
Long-term debt, net of unamortized discounts of $20,652 and $23,007	318,098	326,993
Deferred revenue	7,710	6,694
Income taxes payable	2,441	2,245
Deferred income taxes	100	99
Other non-current liabilities	12,035	12,618
Total non-current liabilities	340,384	348,649
Total liabilities	549,268	600,678
Current portion of long-term debt conversion obligation		39,841
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; 33,700 and 32,261 shares outstanding	689	672
Common stock warrants; zero and 1,426 warrants vested; 1,425 and 2,851 issued		16,007
Additional paid-in capital	421,638	391,209
Treasury stock, at cost; 33,830 and 34,919 shares	(804,650)	(826,002)
Accumulated other comprehensive income (loss):
Unrealized loss on short-term investments, net of tax	(12)	(159)
Cumulative foreign currency translation adjustments	(35,649)	(45,213)
Accumulated earnings	733,110	714,846
Total stockholders' equity	315,126	251,360
Total liabilities, current portion of long-term debt conversion obligation and stockholders' equity	864,394	891,879
Software
Non-current assets:
Intangible assets	28,890	30,427
Client contracts
Non-current assets:
Intangible assets	$ 38,089	$ 40,675