Statement of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Cash flows from operating activities:
Net income	$ 8,364	$ 20,923
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	6,358	6,807
Provision for receivable allowances	6,217	4,880
Net change in inventory provision	337	322
Foreign currency adjustments on intercompany amounts	(470)	(757)
Stock-based compensation	2,131	1,582
Loss on investments and disposal of fixed assets	31	124
Changes in operating assets and liabilities:
Accounts receivable	3,468	(6,288)
Inventories	(4,696)	(5,480)
Prepaid expenses and other current assets	(1,239)	1,102
Other assets	415	121
Accounts payable	(104)	152
Accrued expenses and other liabilities	(2,497)	5,984
Pension liabilities	(433)	(402)
Net cash provided by operating activities	17,882	29,070
Cash flows from investing activities:
Change in restricted cash	(55)	11
Purchases of investments	(4,517)	(188)
Purchases of property and equipment	(2,780)	(6,296)
Proceeds from sale of investments	387	25
Net cash used in investing activities	(6,965)	(6,448)
Cash flows from financing activities:
Principal payments on capital lease obligations	(1,435)	(1,671)
Repayments of loans and notes payable	(1,174)	(705)
Proceeds from loans	0	423
Proceeds from employee equity plans	762	1,795
Purchases of treasury stock	(2,118)	(7,037)
Net cash used in financing activities	(3,965)	(7,195)
Effect of exchange rate fluctuations on cash and cash equivalents	(869)	(747)
Net increase in cash and cash equivalents	6,083	14,680
Cash and cash equivalents at beginning of period	98,604	75,406
Cash and cash equivalents at end of period	$ 104,687	$ 90,086

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).