Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 232,682	$ 134,279
Accounts receivable (less allowance for losses and sales adjustments of $5,738 in 2019 and $4,647 in 2018)	374,089	298,912
Short-term investments	39,399	44,306
Prepaid expenses	24,717	33,258
Income tax receivable	6,482	4,697
Other current assets	2,328	3,406
Total current assets	679,697	518,858
Accounts receivable, long-term	22,432	16,020
Operating lease right-of-use assets	18,992
Property and equipment, net	171,861	155,177
Other assets:
Goodwill	840,117	753,718
Other intangibles, net	378,914	276,852
Non-current investments and other assets	79,601	70,338
Total assets	2,191,614	1,790,963
Current liabilities:
Accounts payable	14,977	6,910
Accrued liabilities	75,234	66,480
Operating lease liabilities	6,387
Deferred revenue	412,495	350,512
Total current liabilities	509,093	423,902
Revolving line of credit	0	0
Deferred revenue, long-term	199	424
Deferred income taxes	48,442	41,791
Operating lease liabilities, long-term	16,822
Commitments and contingencies
Shareholders' equity:
Preferred stock, $10.00 par value; 1,000,000 shares authorized; none issued	0	0
Common stock, $0.01 par value; 100,000,000 shares authorized; 48,147,969 shares issued in 2019 and 2018	481	481
Additional paid-in capital	739,478	731,435
Accumulated other comprehensive loss, net of tax	(46)	(46)
Retained earnings	917,336	771,925
Treasury stock, at cost; 8,839,352 and 9,872,505 shares in 2019 and 2018, respectively	(40,191)	(178,949)
Total shareholders' equity	1,617,058	1,324,846
Liabilities and Shareholders' equity, Total	$ 2,191,614	$ 1,790,963