CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Cash flows from operating activities
Net income	$ 12,497	$ 50,089
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	10,621	8,312
Stock-based compensation	4,924	3,616
Amortization of premium on marketable securities	1,244	921
Undistributed earnings of joint ventures	(1,420)	(718)
(Gain) loss on disposal of long-lived assets	(47)	14
Changes in operating assets and liabilities, net of acquisitions and disposals:
Accounts receivable	(2,951)	(6,199)
Inventories	3,540	(9,744)
Prepaid expenses and other current assets	(732)	2,853
Accounts payable	5,894	(4,807)
Deferred revenue	(3,949)	92
Accrued warranty and retrofit costs	(172)	(538)
Accrued compensation and benefits	(5,630)	(2,443)
Accrued restructuring costs	(168)	(1,956)
Accrued expenses and other current liabilities	(1,954)	(574)
Net cash provided by operating activities	21,697	38,918
Cash flows from investing activities
Purchases of property, plant and equipment	(4,384)	(3,175)
Purchases of marketable securities	(39,097)	(71,225)
Sale/maturity of marketable securities	61,970	37,551
Acquisition, net of cash acquired	(8,716)
Decrease (increase) in restricted cash	476	(3,788)
Net cash provided by (used in) investing activities	10,249	(40,637)
Cash flows from financing activities
Proceeds from the issuance of common stock, net of issuance costs	842	681
Common stock dividend paid	(10,442)
Net cash (used in) provided by financing activities	(9,600)	681
Effects of exchange rate changes on cash and cash equivalents	(24)	543
Net increase (decrease) in cash and cash equivalents	22,322	(495)
Cash and cash equivalents, beginning of period	58,833	59,823
Cash and cash equivalents, end of period	$ 81,155	$ 59,328

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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).