Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Mar. 31, 2020
Current assets:
Cash and cash equivalents	$ 415,719	$ 338,489
Marketable securities	12,127	47,969
Accounts receivable and unbilled costs, net of allowance for doubtful accounts of $782 and $1,350 at September 30, 2020 and March 31, 2020, respectively	169,687	213,514
Inventories and deferred costs	26,223	22,227
Prepaid income taxes	8,998	13,505
Prepaid expenses and other current assets	36,654	24,039
Total current assets	669,408	659,743
Fixed assets, net	53,168	57,715
Operating lease right-of-use assets	65,562	68,583
Goodwill	1,718,595	1,725,680
Intangible assets, net	551,783	582,179
Deferred income taxes	6,690	6,220
Long-term marketable securities	0	2,613
Other assets	12,345	17,770
Total assets	3,077,551	3,120,503
Current liabilities:
Accounts payable	18,083	20,004
Accrued compensation	61,842	75,632
Accrued other	34,484	21,840
Income taxes payable	233	903
Deferred revenue and customer deposits	236,240	270,281
Current portion of operating lease liabilities	11,325	10,337
Total current liabilities	362,207	398,997
Other long-term liabilities	14,646	10,039
Deferred tax liability	108,716	114,394
Accrued long-term retirement benefits	36,408	34,256
Long-term deferred revenue and customer deposits	99,581	104,240
Operating lease liabilities, net of current portion	66,673	70,658
Long-term debt	450,000	450,000
Total liabilities	1,138,231	1,182,584
Commitments and contingencies (Note 14)
Preferred stock, $0.001 par value:
5,000,000 shares authorized; no shares issued or outstanding at September 30, 2020 and March 31, 2020	0	0
Common stock, $0.001 par value:
300,000,000 shares authorized; 123,840,945 and 122,006,077 shares issued and 73,574,035 and 72,220,906 shares outstanding at September 30, 2020 and March 31, 2020, respectively	123	122
Additional paid-in capital	2,924,757	2,891,553
Accumulated other comprehensive loss	(1,258)	(3,160)
Treasury stock at cost, 50,266,910 and 49,785,171 shares at September 30, 2020 and March 31, 2020, respectively	(1,318,535)	(1,305,935)
Retained earnings	334,233	355,339
Total stockholders' equity	1,939,320	1,937,919
Total liabilities and stockholders' equity	$ 3,077,551	$ 3,120,503