Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current assets:
Cash and cash equivalents	$ 369,821	$ 304,880
Marketable securities	77,941	137,892
Accounts receivable and unbilled costs, net of allowance for doubtful accounts of $1,991 and $2,066 at March 31, 2018 and 2017, respectively	213,438	294,374
Inventories and deferred costs	34,774	40,002
Prepaid income taxes	22,932	40,346
Prepaid expenses and other current assets (related party balances of $3,187 and $3,585 at March 31, 2018 and 2017, respectively)	33,502	36,972
Total current assets	752,408	854,466
Fixed assets, net	52,511	61,393
Goodwill	1,712,764	1,718,162
Intangible assets, net	831,374	931,269
Deferred income taxes	6,685	6,580
Long-term marketable securities	0	21,933
Other assets	12,866	7,710
Total assets	3,368,608	3,601,513
Current liabilities:
Accounts payable (related party balances of $369 and $444 at March 31, 2018 and 2017, respectively)	30,133	37,407
Accrued compensation	46,552	77,607
Accrued other	33,164	29,522
Income taxes payable	1,526	5,057
Deferred revenue and customer deposits	301,925	310,594
Total current liabilities	413,300	460,187
Other long-term liabilities	8,308	3,976
Deferred tax liability	151,563	277,599
Accrued long-term retirement benefits	35,246	32,117
Long-term deferred revenue and customer deposits	91,409	86,595
Long-term debt	600,000	300,000
Contingent liabilities, net of current portion	0	4,789
Total liabilities	1,299,826	1,165,263
Commitments and contingencies (Note 17)
Stockholders’ equity:
Preferred stock, $0.001 par value: 5,000,000 shares authorized; no shares issued or outstanding at March 31, 2018 and 2017	0	0
Common stock, $0.001 par value: 300,000,000 shares authorized; 117,744,913 and 115,917,431 shares issued and 80,270,023 and 92,041,288 shares outstanding at March 31, 2018 and 2017, respectively	117	116
Additional paid-in capital	2,665,120	2,693,846
Accumulated other comprehensive income (loss)	2,895	(3,472)
Treasury stock at cost, 37,474,890 and 23,876,143 shares at March 31, 2018 and 2017, respectively	(995,843)	(570,921)
Retained earnings	396,493	316,681
Total stockholders’ equity	2,068,782	2,436,250
Total liabilities and stockholders’ equity	$ 3,368,608	$ 3,601,513

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.