CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 301,985	$ 232,682
Accounts receivable (less allowance for losses and sales adjustments of $6,470 in 2020 and $5,738 in 2019)	318,144	374,089
Short-term investments	38,250	39,399
Prepaid expenses	33,964	24,717
Income tax receivable	16,657	6,482
Other current assets	3,220	2,328
Total current assets	712,220	679,697
Accounts receivable, long-term	21,394	22,432
Operating lease right-of-use assets	17,992	18,992
Property and equipment, net	175,460	171,861
Other assets:
Goodwill	840,028	840,117
Other intangibles, net	366,506	378,914
Non-current investments and other assets	85,776	79,601
Total assets	2,219,376	2,191,614
Current liabilities:
Accounts payable	12,958	14,977
Accrued liabilities	59,765	75,234
Operating lease liabilities	6,373	6,387
Current income tax payable	0	0
Deferred revenue	365,959	412,495
Total current liabilities	445,055	509,093
Revolving line of credit	0	0
Deferred revenue, long-term	167	199
Deferred income taxes	45,774	48,442
Operating lease liabilities, long-term	15,548	16,822
Commitments and contingencies	0	0
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 and outstanding as of March 31, 2020 and December 31, 2019	481	481
Additional paid-in capital	798,089	739,478
Accumulated other comprehensive loss, net of tax	(46)	(46)
Retained earnings	964,886	917,336
Treasury stock, at cost; 8,397,086 and 8,839,352 shares in 2020 and 2019, respectively	(50,578)	(40,191)
Total shareholders' equity	1,712,832	1,617,058
Total liabilities and shareholders' equity	$ 2,219,376	$ 2,191,614