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Represents the maximum self-insurance for future claims per claim held by the entity.

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Represents the minimum number of additional employees hired and trained than anticipated.

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Represents the percentage of maximum sales not accounted for by a single customer.

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Revenue from sale of goods and services rendered during the reporting period from Department of Defense, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Revenue from sale of goods and services rendered during the reporting period from Department of Defense of the domestic country in which the entity operates, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Revenue from sale of goods and services rendered during the reporting period from Department of Defense of the foreign country, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Represents the unplanned start-up cost incurred by the entity due to issues associated with the building to the DoD's technical data package and complying with new requirements in the contract.

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The percentage of employees covered by a collective bargaining agreement as of the balance sheet date, when it serves as a benchmark in a concentration of risk calculation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The carrying amount as of the balance sheet date of the combined total of loss contingency liabilities.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Losses recognized in the current period on contracts which are expected to generate losses, which are probable and can be reasonably estimated, in a future period.

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Contingencies, Significant Estimates and Concentrations (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended									1 Months Ended	12 Months Ended	1 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009	Sep. 30, 2011 Environmental matters	Sep. 30, 2010 Environmental matters	Sep. 30, 2011 Personal Injury Actions and Other	Sep. 30, 2010 Personal Injury Actions and Other	Sep. 30, 2011 Performance and specialty bonds	Sep. 30, 2011 Standby letters of credit	Aug. 31, 2009 FMTV program Employee	Sep. 30, 2011 FMTV program team	Jan. 31, 2010 Controls Solutions LLC suit
Loss contingencies
Reserve for loss contingencies				$ 2.1	$ 1.9	$ 41.7	$ 44.4
Maximum self-insurance available per claim						3.0
Commitments and contingencies								284.0	27.9
Approximate percentage of workforce covered under collective bargaining agreements (as a percent)	26.00%
Damages asserted												190.3
Minimum number of additional employees hired and trained than anticipated										500
Unplanned start-up cost											43.0
Loss on contract											44.4
Number of integrated project teams											11
Increase in material costs due to 1% escalation in material costs											24
Significant portion of revenue from DoD
DoD	4,136.8	7,054.7	2,738.9
Foreign military sales	74.3	28.3	26.8
Total DoD sales	$ 4,211.1	$ 7,083.0	$ 2,765.7
Percentage of maximum sales not accounted for by single customer (as a percent)	10.00%	10.00%	10.00%