Detail of Selected Balance Sheet Accounts (Cost and Estimated Earnings on Uncompleted Contracts) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Balance Sheet Related Disclosures [Abstract]
Costs incurred on uncompleted contracts	$ 604,939	$ 618,570
Estimated earnings	157,562	159,962
Total	762,501	778,532
Less: Billings to date	(715,233)	(747,446)
Net underbilled position	47,268	31,086
Included in the accompanying balance sheets under the following captions:
Costs and estimated earnings in excess of billings on uncompleted contracts – underbilled	95,970	79,420
Billings in excess of costs and estimated earnings on uncompleted contracts – overbilled	(48,702)	(48,334)
Net underbilled position	$ 47,268	$ 31,086

Costs incurred on uncompleted contracts.

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Estimated earnings.

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Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method.

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Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings which is expected to be collected within one year or the normal operating cycle, if longer.

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Amount to be collected within one year of the balance sheet date (or one operating cycle, if longer) from customers in accordance with the contractual provisions of long-term contracts or programs including amounts billed and unbilled as of the balance sheet date.

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Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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