Other Financial Data (Schedule Of Other Financial Data) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Component of Operating Other Cost and Expense [Line Items]
Salaries and wages (including fringes)	$ 187,214	$ 160,780	$ 153,416
Maintenance and repairs	4,530	3,440	3,807
Research and development	42,101	36,234	34,911
Other engineering costs	11,490	13,250	14,370
Total R&D and Other engineering costs	53,591	49,484	49,281
As a % of net sales	7.70%	8.10%	8.00%
Company-Sponsored [Member]
Component of Operating Other Cost and Expense [Line Items]
Research and development	33,574	32,199	31,974
Customer-Sponsored [Member]
Component of Operating Other Cost and Expense [Line Items]
Research and development	$ 8,527	$ 4,035	$ 2,937

Other engineering costs.

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Percentage of total research and development and other engineering costs on net sales.

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Research and development and other engineering costs.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Expenditures for salaries other than officers. Does not include allocated share-based compensation, pension and post-retirement benefit expense or other labor-related non-salary expense. For commercial and industrial companies, excludes any direct and overhead labor that is included in cost of goods sold.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The amount of operating expenses for the period that are associated with the utility's normal revenue producing operation; including selling, general, and administrative expenses, costs incurred for routine plant repairs and maintenance, and operations.

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