Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Operating Activities:
Net income (loss)	$ (239)us-gaap_NetIncomeLoss	$ 8,255us-gaap_NetIncomeLoss
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation	3,318us-gaap_Depreciation	2,562us-gaap_Depreciation
Amortization	118us-gaap_AdjustmentForAmortization	416us-gaap_AdjustmentForAmortization
Stock-based compensation	1,116us-gaap_ShareBasedCompensation	1,185us-gaap_ShareBasedCompensation
Bad debt expense	283us-gaap_ProvisionForDoubtfulAccounts	15us-gaap_ProvisionForDoubtfulAccounts
Deferred income tax benefit	(317)us-gaap_DeferredIncomeTaxExpenseBenefit	(2,362)us-gaap_DeferredIncomeTaxExpenseBenefit
Gain on amended supply agreement	(507)us-gaap_OtherNoncashIncome
Cash received from amended supply agreement		10,000
Changes in operating assets and liabilities:
Accounts receivable, net	(25,674)	7,577
Costs and billings in excess of estimates on uncompleted contracts	20,943	(13,399)
Inventories	(3,998)us-gaap_IncreaseDecreaseInInventories	405us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other current assets	467	1,631
Accounts payable and income taxes payable	(5,462)	1,053
Accrued liabilities	(12,793)	(12,145)
Other, net	17	156
Net cash provided by (used in) operating activities	(22,728)	5,349
Investing Activities:
Proceeds from sale of property, plant and equipment	31
Purchases of property, plant and equipment	(18,962)	(5,764)
Net cash used in investing activities	(18,931)	(5,764)
Financing Activities:
Payments on industrial development revenue bonds	(400)us-gaap_RepaymentsOfLongTermDebt	(400)us-gaap_RepaymentsOfLongTermDebt
Shares withheld in lieu of employee tax withholding	(454)	(524)
Dividends paid	(3,128)us-gaap_PaymentsOfDividendsCommonStock	(2,993)us-gaap_PaymentsOfDividendsCommonStock
Payments on short-term and other financing		(16)
Net cash used in financing activities	(3,982)	(3,933)
Net increase (decrease) in cash and cash equivalents	(45,641)	(4,348)
Effect of exchange rate changes on cash and cash equivalents	(1,013)	661
Cash and cash equivalents, beginning of period	103,118	107,411
Cash and cash equivalents, end of period	$ 56,464	$ 103,724

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