Accounts Receivable - Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jul. 01, 2018	Jul. 01, 2018	Jul. 02, 2017	Oct. 01, 2017
Accounts Receivable - Net and Revenue Recognition
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	$ 68.0	$ 68.0		$ 59.0
Gains (losses) from claim settlement		0.0
Billed accounts receivable related to U.S. federal government contracts	93.5	93.5		45.4
U.S. federal government unbilled receivables	98.0	98.0		109.7
Net unfavorable operating income adjustments			$ 8.0
Liabilities for anticipated losses	5.0	5.0		$ 8.1
Estimated cost to complete the related contracts	10.8	10.8
CIG
Accounts Receivable - Net and Revenue Recognition
Net unfavorable operating income adjustments	1.0	2.4	2.3
RCM
Accounts Receivable - Net and Revenue Recognition
Gains (losses) from claim settlement	(0.4)	(3.6)
Reduction in the revenue related to the evaluation of the claims	$ 0.4	$ 4.9
Net unfavorable operating income adjustments			$ 5.7

Represents the period within which the majority of billings in excess of costs on uncompleted contracts will be earned.

No definition available.

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- Definition

Contract Receivable Decrease In Revenue Related To Claims And Requests For Equitable Adjustment On Contract

+ References

No definition available.

+ Details

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- Definition

The amount of billed receivables that are derived from government contracts.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the unbilled accounts receivable related to claims and requests for equitable adjustment on contracts.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of remaining estimated costs to complete the contracts.

+ References

No definition available.

+ Details

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- Definition

Revenue Recognition Net Unfavorable Operating Income Adjustments

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the period within which substantially all unbilled receivables are expected to be billed and collected.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

Unbilled amounts (net of unliquidated progress payments) of government contract receivables.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Cumulative provision for contract losses not offset against related costs accumulated on the balance sheet.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 35
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=68068069&loc=d3e57777-111642

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