Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands	3 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Cash flows from operating activities:
Net (loss) income	$ (37,679)	$ 9,170
Adjustments to reconcile net (loss) income to net cash used in operations:
Depreciation and amortization	3,242	2,654
Stock-based compensation expense	3,466	3,578
Provision for excess and obsolete inventory	413
Losses on purchase commitments	1,071
Allowance for doubtful accounts		957
Deferred income taxes		2,027
Other non-cash items	827	320
Changes in operating asset and liability accounts:
Accounts receivable	670	(35,848)
Inventory	(5,324)	(5,654)
Prepaid expenses and other current assets	(7,812)	(1,616)
Accounts payable and accrued expenses	(19,732)	(2,140)
Deferred revenue	3,084	8,073
Net cash used in operating activities	(57,774)	(18,479)
Cash flows from investing activities:
Purchase of property, plant and equipment	(4,498)	(8,185)
Purchase of marketable securities		(15,061)
Proceeds from maturities of marketable securities	90,800	24,189
Change in restricted cash	(3,763)	257
Purchase of intangible assets	(240)	(1,230)
Purchase of minority investments	(1,800)
Advanced payment for planned acquisition	(20,551)
Change in other assets	(195)	(11)
Net cash provided by (used in) investing activities	59,753	(41)
Cash flows from financing activities:
Payments in lieu of issuance of common stock for payroll taxes	(271)
Net borrowings on lines of credit	4,626
Proceeds from exercise of employee stock options and ESPP	21	561
Net cash provided by financing activities	4,376	561
Effect of exchange rate changes on cash and cash equivalents	747	(4,791)
Net increase in cash and cash equivalents	7,102	(22,750)
Cash and cash equivalents at beginning of period	123,783	87,594
Cash and cash equivalents at end of period	130,885	64,844
Supplemental schedule of cash flow information:
Cash paid for income taxes	12,485	4,453
Non-cash contingent consideration in connection with acquisitions		4,004
Non-cash issuance of common stock	$ 205	$ 189

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