Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net income (loss)	$ 35,874	$ 19,352	$ (2,754)
Adjustments to reconcile net income (loss) to cash provided by operating activities, net of the effects of acquisitions:
Depreciation and amortization	95,784	105,828	116,104
Loss on extinguishment of debt	596	0	0
Operating lease right-of-use assets	10,292	10,004	10,504
Loss on disposal of fixed assets	5	236	16
Share-based compensation expense associated with equity awards	56,074	51,892	50,861
Net change in fair value of contingent and contractual liabilities	(837)	0	798
Accretion of contingent consideration	0	0	(36)
Deferred income taxes	(12,681)	(23,804)	(9,821)
Other gains	(11)	(196)	(152)
Changes in assets and liabilities
Accounts receivable and unbilled costs	49,322	16,878	21,472
Inventories	(7,996)	(2,043)	1,501
Prepaid expenses and other assets	(13,001)	11,483	13,839
Accounts payable	4,211	(1,734)	(4,288)
Accrued compensation and other expenses	2,391	31,955	32,812
Operating lease liabilities	(12,060)	(10,307)	(13,077)
Income taxes payable	(3,087)	6,684	(919)
Deferred revenue	91,137	(2,307)	8,163
Net cash provided by operating activities	296,013	213,921	225,023
Cash flows from investing activities:
Purchase of marketable securities	(78,367)	(15,673)	(117,383)
Proceeds from maturity of marketable securities	20,569	56,806	144,322
Purchase of fixed assets	(10,350)	(11,986)	(19,922)
Purchase of intangible assets	(50)	(4,537)	0
Acquisition of businesses, net of cash acquired	0	0	(11,347)
(Increase) decrease in deposits	(155)	88	(31)
Collection of contingent consideration		0	52
Net cash (used in) provided by investing activities	(68,353)	24,698	(4,309)
Cash flows from financing activities:
Issuance of common stock under stock plans	2	2	2
Payment of contingent consideration	0	(1,748)	0
Treasury stock repurchases	(35,653)	(3,275)	(175,000)
Tax withholding on restricted stock units	(15,691)	(13,286)	(11,872)
Payment of debt issuance costs	(3,660)	0	0
Repayment of long-term debt	(350,000)	(100,000)	(100,000)
Proceeds from issuance of long-term debt	350,000	0	0
Collection of contingent consideration	837	0	0
Net cash used in financing activities	(54,165)	(118,307)	(286,870)
Effect of exchange rate changes on cash and cash equivalents	(4,510)	6,627	(3,427)
Net increase (decrease) in cash and cash equivalents	168,985	126,939	(69,583)
Cash and cash equivalents and restricted cash, beginning of year	467,176	340,237	409,820
Cash and cash equivalents and restricted cash, end of year	636,161	467,176	340,237
Supplemental disclosures of cash flow information:
Cash paid for interest	4,962	7,685	17,644
Cash paid for income taxes	31,702	11,472	13,061
Non-cash transactions:
Transfers of inventory to fixed assets	2,657	1,530	2,290
Additions to property, plant and equipment included in accounts payable	197	333	255
Issuance of common stock under employee stock purchase plans	14,582	14,429	14,227
Contingent consideration related to acquisition, included in accrued other	$ 0	$ 0	$ 1,800