CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 667,667	$ 912,672
Short-term investments	361	479
Accounts receivable, less allowance for doubtful accounts of $14,600 and $14,000, respectively	645,891	537,564
Other receivables and current assets	324,655	268,522
Total current assets	1,638,574	1,719,237
Long-term assets:
Property and equipment, net	87,914	96,503
Operating lease right-of-use assets	120,881	137,730
Goodwill	3,409,271	3,038,306
Other intangible assets, net	763,119	694,865
Other long-term assets	279,676	225,119
Deferred income taxes	24,879	28,830
Total long-term assets	4,685,740	4,221,353
Total assets	6,324,314	5,940,590
Current liabilities:
Accounts payable	10,863	18,691
Accrued bonuses and commissions	163,182	112,491
Accrued income taxes	8,410	26,116
Other accrued expenses and liabilities	204,509	199,466
Deferred revenue	391,528	372,061
Total current liabilities	778,492	728,825
Long-term liabilities:
Deferred income taxes	105,548	110,321
Long-term operating lease liabilities	104,378	120,940
Long-term debt	753,576	798,118
Other long-term liabilities	98,272	84,514
Total long-term liabilities	1,061,774	1,113,893
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.01 par value; 2,000,000 shares authorized; zero shares issued or outstanding	0	0
Common stock, $0.01 par value; 300,000,000 shares authorized; 95,267,307 and 95,266,320 shares issued, respectively	953	953
Additional paid-in capital	1,465,694	1,434,203
Retained earnings	4,259,220	3,804,593
Treasury stock, at cost: 8,188,331 and 8,693,809 shares, respectively	(1,185,707)	(1,124,102)
Accumulated other comprehensive loss	(56,112)	(17,775)
Total stockholders' equity	4,484,048	4,097,872
Total liabilities and stockholders' equity	$ 6,324,314	$ 5,940,590