CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 23,314	$ 33,087
Accounts receivable (less allowance for losses of $2,657 in 2016 and $1,640 in 2015)	188,429	176,360
Short-term investments	23,764	13,423
Prepaid expenses	21,384	22,334
Income tax receivable	17,680	21,080
Other current assets	2,756	1,931
Total current assets	277,327	268,215
Accounts receivable, long-term	2,744	2,777
Property and equipment, net	120,963	101,112
Other assets:
Goodwill	647,525	653,666
Other intangibles, net	276,326	295,378
Non-current investments and other assets	27,881	35,422
Total assets	1,352,766	1,356,570
Current liabilities:
Accounts payable	5,992	6,789
Accrued liabilities	54,184	49,156
Deferred revenue	288,316	281,627
Total current liabilities	348,492	337,572
Revolving line of credit	34,000	66,000
Deferred revenue, long-term	2,924	3,115
Deferred income taxes	85,095	91,026
Commitments and contingencies
Shareholders' equity:
Preferred stock, $10.00 par value; 1,000,000 shares authorized; none issued
Common stock, $0.01 par value; 100,000,000 shares authorized; 48,147,969 shares issued and outstanding as of September 30, 2016 and December 31, 2015	481	481
Additional paid-in capital	595,162	607,755
Accumulated other comprehensive loss, net of tax	(46)	(46)
Retained earnings	384,234	326,019
Treasury stock, at cost; 11,532,984 and 11,373,666 shares in 2016 and 2015, respectively	(97,576)	(75,352)
Total shareholders' equity	882,255	858,857
Liabilities and Shareholders' equity, Total	$ 1,352,766	$ 1,356,570

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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Namespace Prefix:	us-gaap_
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.