Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Mar. 31, 2021
Current assets:
Cash and cash equivalents	$ 468,470	$ 467,176
Marketable securities	7,347	9,277
Accounts receivable and unbilled costs, net of allowance for doubtful accounts of $398 and $416 at September 30, 2021 and March 31, 2021, respectively	162,888	197,717
Inventories and deferred costs	25,728	22,813
Prepaid income taxes	11,526	1,906
Prepaid expenses and other current assets	25,629	23,583
Total current assets	701,588	722,472
Fixed assets, net	45,008	48,474
Operating lease right-of-use assets	56,715	61,512
Goodwill	1,717,870	1,717,554
Intangible assets, net	474,448	511,866
Deferred income taxes	8,064	8,096
Other assets	12,705	15,064
Total assets	3,016,398	3,085,038
Current liabilities:
Accounts payable	17,644	17,964
Accrued compensation	57,783	83,057
Accrued other	31,802	21,127
Income taxes payable	4,840	7,025
Deferred revenue and customer deposits	246,726	269,748
Current portion of operating lease liabilities	11,992	12,354
Total current liabilities	370,787	411,275
Other long-term liabilities	12,315	21,641
Deferred tax liability	85,987	92,287
Accrued long-term retirement benefits	39,704	39,479
Long-term deferred revenue and customer deposits	102,457	103,310
Operating lease liabilities, net of current portion	56,144	61,267
Long-term debt	350,000	350,000
Total liabilities	1,017,394	1,079,259
Commitments and contingencies (Note 12)
Preferred stock, $0.001 par value:
5,000,000 shares authorized; no shares issued or outstanding at September 30, 2021 and March 31, 2021	0	0
Common stock, $0.001 par value:
300,000,000 shares authorized; 126,108,858 and 124,197,974 shares issued and 74,217,661 and 73,751,615 shares outstanding at September 30, 2021 and March 31, 2021, respectively	126	124
Additional paid-in capital	2,991,704	2,955,400
Accumulated other comprehensive loss	(1,931)	(1,940)
Treasury stock at cost, 51,891,197 and 50,446,359 shares at September 30, 2021 and March 31, 2021, respectively	(1,362,141)	(1,322,496)
Retained earnings	371,246	374,691
Total stockholders' equity	1,999,004	2,005,779
Total liabilities and stockholders' equity	$ 3,016,398	$ 3,085,038