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Accounts Receivable - Net and Revenue Recognition (Details) - USD ($) $ in Millions | 12 Months Ended
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Oct. 01, 2017 | Oct. 02, 2016 | Sep. 27, 2015
Financial information concerning reportable segments |  |  |
Period for billing and collecting unbilled receivables | 12 months |  |
Period for earning majority of billings in excess of costs | 12 months |  |
Unbilled accounts receivable related to claims and requests for equitable adjustment on contracts | $ 59.0 | $ 45.0 |
Billed accounts receivable related to U.S. federal government contracts | 45.4 | 47.4 |
U.S. federal government unbilled receivables | $ 109.7 | $ 92.2 |
Threshold percentage for disclosure of accounts receivable from a single client | 10.00% | 10.00% |
Net unfavorable operating income adjustments | $ 8.0 |  | $ 8.9
Liability for anticipated losses | 8.1 | $ 6.7 |
Estimated cost to complete the related contracts | 5.0 |  |
RCM |  |  |
Financial information concerning reportable segments |  |  |
Reduction in the revenue related to the evaluation of the claims | 4.9 |  |
Gain (loss) from claim settlement | (3.6) | 4.6 |
Cash proceeds from claim settlement |  | 13.4 |
Claims settlement amount |  | 8.8 |
Decrease in operating income related to the increase in allowance for doubtful accounts |  | 7.9 |
Increase in allowance for doubtful accounts |  | 7.9 |
Collectability of certain accounts receivable |  | 4.6 |
Net unfavorable operating income adjustments | 5.7 | $ 2.3 |
RME |  |  |
Financial information concerning reportable segments |  |  |
Net unfavorable operating income adjustments | $ 2.3 |  |

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- Definition Represents the period within which the majority of billings in excess of costs on uncompleted contracts will be earned. + References No definition available. + Details
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- Definition The minimum percentage of accounts receivable from a single client that is used as a threshold for disclosure of a concentration of risk. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
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