Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Current assets:
Cash and cash equivalents	$ 338,489	$ 409,632
Marketable securities	47,969	76,344
Accounts receivable and unbilled costs, net of allowance for doubtful accounts of $1,350 and $1,583 at March 31, 2020 and 2019, respectively	213,514	235,318
Inventories and deferred costs	22,227	26,270
Prepaid income taxes	13,505	18,000
Prepaid expenses and other current assets	24,039	35,658
Total current assets	659,743	801,222
Fixed assets, net	57,715	58,951
Operating lease right-of-use assets	68,583
Goodwill	1,725,680	1,715,485
Intangible assets, net	582,179	669,118
Deferred income taxes	6,220	7,218
Long-term marketable securities	2,613	1,012
Other assets	17,770	16,988
Total assets	3,120,503	3,269,994
Current liabilities:
Accounts payable	20,004	24,582
Accrued compensation	75,632	58,501
Accrued other	21,840	23,027
Income taxes payable	903	1,318
Deferred revenue and customer deposits	270,281	272,508
Current portion of operating lease liabilities	10,337
Total current liabilities	398,997	379,936
Other long-term liabilities	10,039	19,493
Deferred tax liability	114,394	124,229
Accrued long-term retirement benefits	34,256	36,284
Long-term deferred revenue and customer deposits	104,240	94,619
Operating lease liabilities, net of current portion	70,658
Long-term debt	450,000	550,000
Total liabilities	1,182,584	1,204,561
Commitments and contingencies (Note 19)
Stockholders’ equity:
Preferred stock, $0.001 par value: 5,000,000 shares authorized; no shares issued or outstanding at March 31, 2020 and 2019	0	0
Common stock, $0.001 par value: 300,000,000 shares authorized; 122,006,077 and 119,760,132 shares issued and 72,220,906 and 77,610,361 shares outstanding at March 31, 2020 and 2019, respectively	122	120
Additional paid-in capital	2,891,553	2,828,922
Accumulated other comprehensive income (loss)	(3,160)	(2,639)
Treasury stock at cost, 49,785,171 and 42,149,771 shares at March 31, 2020 and 2019, respectively	(1,305,935)	(1,119,063)
Retained earnings	355,339	358,093
Total stockholders’ equity	1,937,919	2,065,433
Total liabilities and stockholders’ equity	$ 3,120,503	$ 3,269,994