Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019
Current assets:
Cash and cash equivalents	$ 287,660	$ 409,632
Marketable securities	56,274	76,344
Accounts receivable and unbilled costs, net of allowance for doubtful accounts of $1,728 and $1,583 at December 31, 2019 and March 31, 2019, respectively	244,877	235,318
Inventories and deferred costs	24,977	26,270
Prepaid income taxes	14,454	18,000
Prepaid expenses and other current assets	25,807	35,658
Total current assets	654,049	801,222
Fixed assets, net	58,700	58,951
Operating lease right-of-use assets	65,738
Goodwill	1,718,496	1,715,485
Intangible assets, net	602,856	669,118
Deferred income taxes	7,034	7,218
Long-term marketable securities	2,561	1,012
Other assets	17,905	16,988
Total assets	3,127,339	3,269,994
Current liabilities:
Accounts payable	19,756	24,582
Accrued compensation	70,430	58,501
Accrued other	20,159	23,027
Income taxes payable	1,517	1,318
Deferred revenue and customer deposits	261,151	272,508
Current portion of operating lease liabilities	11,091
Total current liabilities	384,104	379,936
Other long-term liabilities	6,997	19,493
Deferred tax liability	115,470	124,229
Accrued long-term retirement benefits	35,808	36,284
Long-term deferred revenue and customer deposits	104,339	94,619
Operating lease liabilities, net of current portion	67,814
Long-term debt	450,000	550,000
Total liabilities	1,164,532	1,204,561
Commitments and contingencies (Note 14)
Preferred stock, $0.001 par value:
5,000,000 shares authorized; no shares issued or outstanding at December 31, 2019 and March 31, 2019	0	0
Common stock, $0.001 par value:
300,000,000 shares authorized; 121,679,117 and 119,760,132 shares issued and 73,855,221 and 77,610,361 shares outstanding at December 31, 2019 and March 31, 2019, respectively	122	120
Additional paid-in capital	2,873,702	2,828,922
Accumulated other comprehensive loss	(3,345)	(2,639)
Treasury stock at cost, 47,823,896 and 42,149,771 shares at December 31, 2019 and March 31, 2019, respectively	(1,255,675)	(1,119,063)
Retained earnings	348,003	358,093
Total stockholders' equity	1,962,807	2,065,433
Total liabilities and stockholders' equity	$ 3,127,339	$ 3,269,994