CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities
Net income	$ 3,006	$ 23,486
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	5,268	4,274
Stock-based compensation	1,743	1,209
Amortization of premium on marketable securities	654	410
Undistributed earnings of joint ventures	(1,225)	(310)
Gain on disposal of long-lived assets		(13)
Changes in operating assets and liabilities, net of acquisitions and disposals:
Accounts receivable	3,935	4,949
Inventories	5,874	(11,289)
Prepaid expenses and other current assets	(490)	2,117
Accounts payable	(5,910)	(3,424)
Deferred revenue	(2,427)	(330)
Accrued warranty and retrofit costs	(152)	(314)
Accrued compensation and benefits	(4,270)	(2,810)
Accrued restructuring costs	32	(985)
Accrued expenses and other current liabilities	(929)	713
Net cash provided by operating activities	5,109	17,683
Cash flows from investing activities
Purchases of property, plant and equipment	(2,063)	(1,638)
Purchases of marketable securities	(23,579)	(38,704)
Sale/maturity of marketable securities	24,549	25,225
Acquisition, net of cash acquired	(8,716)
Decrease in restricted cash	430
Net cash used in investing activities	(9,379)	(15,117)
Cash flows from financing activities
Common stock dividend paid	(5,185)
Net cash used in financing activities	(5,185)
Effects of exchange rate changes on cash and cash equivalents	(165)	(77)
Net increase (decrease) in cash and cash equivalents	(9,620)	2,489
Cash and cash equivalents, beginning of period	58,833	59,823
Cash and cash equivalents, end of period	$ 49,213	$ 62,312

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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).