Statement of Cash Flows (USD $) In Thousands	6 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net income	$ 20,923	$ 13,407
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	6,807	9,370
Provision for receivable allowances	4,880	3,878
Net change in inventory provision	322	(3,279)
Foreign currency adjustments on intercompany amounts	(757)	(454)
Stock-based compensation	1,582	1,633
Loss on investments and disposal of fixed assets	124	448
Changes in operating assets and liabilities:
Accounts receivable	(6,288)	(7,134)
Inventories	(5,480)	(7,486)
Prepaid expenses and other current assets	1,102	(339)
Other assets	121	(261)
Accounts payable	152	(1,525)
Accrued expenses and other liabilities	5,984	5,548
Pension liabilities	(402)	(205)
Net cash provided by operating activities	29,070	13,601
Cash flows from investing activities:
Change in restricted cash	11	(113)
Purchases of investments	(188)	(121)
Purchases of property and equipment	(6,296)	(3,940)
Proceeds from sale of investments	25	0
Net cash used in investing activities	(6,448)	(4,174)
Cash flows from financing activities:
Principal payments on capital lease obligations	(1,671)	(1,530)
Repayments of loans and notes payable	(705)	(681)
Proceeds from loan	423	0
Proceeds from employee equity plans	1,795	593
Purchase of treasury stock	(7,037)	(3,665)
Net cash used in financing activities	(7,195)	(5,283)
Effect of exchange rate fluctuations on cash and cash equivalents	(747)	708
Net increase in cash and cash equivalents	14,680	4,852
Cash and cash equivalents at beginning of period	75,406	60,524
Cash and cash equivalents at end of period	$ 90,086	$ 65,376