CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 216,773	$ 603,623
Accounts receivable (less allowance for losses and sales adjustments of $8,087 in 2021 and $9,255 in 2020)	584,156	382,319
Short-term investments	51,223	72,187
Prepaid expenses	52,413	30,864
Income tax receivable	20,404	21,598
Other current assets	3,959	2,479
Total current assets	928,928	1,113,070
Accounts receivable, long-term	15,744	21,417
Operating lease right-of-use assets	28,230	18,734
Property and equipment, net	177,712	168,004
Other assets:
Software development costs, net	17,179	9,121
Goodwill	2,309,434	838,428
Other intangibles, net	1,045,580	322,068
Non-current investments	79,057	82,640
Other non-current assets	39,139	33,792
Total assets	4,641,003	2,607,274
Current liabilities:
Accounts payable	106,727	14,011
Accrued liabilities	134,904	83,084
Operating lease liabilities	9,666	5,904
Deferred revenue	484,482	461,278
Current portion of term loans	30,000	0
Total current liabilities	765,779	564,277
Revolving credit facility	65,000	0
Term loans	862,559	0
Convertible senior notes, net	591,906	0
Deferred revenue, long-term	68	100
Deferred income taxes	220,680	40,507
Operating lease liabilities, long-term	22,118	16,279
Other long-term liabilities	4,902	0
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 June 30, 2021 and December 31, 2020	481	481
Additional paid-in capital	962,557	905,332
Accumulated other comprehensive loss, net of tax	(46)	(46)
Retained earnings	1,174,662	1,112,156
Treasury stock, at cost; 7,315,159 and 7,608,627 shares in 2021 and 2020, respectively	(29,663)	(31,812)
Total shareholders' equity	2,107,991	1,986,111
Total liabilities and shareholders' equity	$ 4,641,003	$ 2,607,274