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Significant Accounting Policies (Details) $ in Billions | 12 Months Ended
--- | ---
Sep. 30, 2014 USD ($) item | Sep. 30, 2013 USD ($) | Sep. 30, 2012 USD ($) | Sep. 30, 2011
Fiscal Year |  |  |  |
Fiscal year period |  | 364 days | 364 days | 364 days
Revenue Recognition |  |  |  |
Other direct costs | $ | $ 3.5 | $ 3.2 | $ 3.0 |
Cost-Plus Contracts |  |  |  |
Number of major types of cost-plus contracts the Company enters into | 2 |  |  |
Fixed Price Contracts |  |  |  |
Number of types of fixed price contracts | 2 |  |  |
Pension Plans |  |  |  |
Amortization period of the difference between actual return and expected return | 5 years |  |  |
Specified percentage to be exceeded for amortization of cumulative, net unrecognized gains or losses (as a percent) | 10.00% |  |  |

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- Definition Represents the amortization period of the difference between the actual return (including capital, dividends, and interest) and the expected return in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Other costs incurred and are directly related to services rendered by an entity during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2(d)) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
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