Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 85,351	$ 82,822
Restricted cash	10,000	11,987
Accounts receivable, net of allowance for doubtful accounts of $699 at March 31, 2018 and $634 at December 31, 2017	34,064	34,461
Income tax refunds receivable	1,920	1,204
Prepaid expenses and other current assets	6,455	5,714
Total current assets	137,790	136,188
Property and equipment, net	16,454	16,763
Goodwill	280,454	279,131
Intangible assets, net	83,503	84,856
Restricted cash	6,000	6,000
Other assets	4,750	3,112
Total assets	528,951	526,050
Current liabilities:
Accounts payable	2,943	1,467
Accrued expenses and other current liabilities	38,127	43,096
Accrued income taxes payable	440	522
Deferred revenue	15,889	15,102
Total current liabilities	57,399	60,187
Revolving line of credit	90,000	93,000
Other long-term liabilities	5,830	6,428
Deferred income taxes	27,135	28,004
Reserve for income taxes	2,811	2,783
Accrued pension benefits	6,507	6,280
Commitments and contingencies (Note 13)
Stockholders' equity:
Preferred stock, $0.001 par value, Authorized shares: 10,000,000; Issued and outstanding: none
Common stock, $0.001 par value, Authorized shares: 250,000,000; Shares issued: 45,587,983 at March 31, 2018 and 44,934,364 at December 31, 2017	44	44
Additional paid-in capital	305,023	298,113
Treasury stock, at cost, 3,419,116 shares at March 31, 2018 and 3,215,644 shares at December 31, 2017	(65,294)	(64,083)
Retained earnings	100,673	97,815
Accumulated other comprehensive loss	(1,177)	(2,521)
Total stockholders' equity	339,269	329,368
Total liabilities and stockholders' equity	$ 528,951	$ 526,050

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.