Basis of Presentation - Contracts accounted for under percentage of completion method (Details) - Contracts accounted for under percentage of completion method $ / shares in Units, $ in Millions	3 Months Ended
Apr. 01, 2017 USD ($) $ / shares	Oct. 01, 2016 item	Apr. 02, 2016 USD ($) $ / shares
Use of Estimates
Change in Accounting Estimate Financial Effect Increase (Decrease) in Income from Continuing Operations before Income Taxes	$ (12)		$ 29
Change in Accounting Estimate Financial Effect Increase (Decrease) in Income from Continuing Operations after taxes	$ (8)		$ 19
Change in Accounting Estimate Financial Effect Increase (Decrease) in Earnings Per Share Diluted \| $ / shares	$ (0.03)		$ 0.07
Gross Favorable Program Profit Adjustments	$ 20		$ 34
Gross Unfavorable Program Profit Adjustments	32		$ 5
Gross unfavorable program profit adjustments related to the Tactical Armoured Patrol Vehicle Program	$ 24
Number of Tactical Armoured Patrol Vehicles (TAPV) under contract to be delivered to Canadian customer \| item		500

Change in accounting estimate financial effect increase (decrease) in earnings per share diluted.

No definition available.

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Change in accounting estimate financial effect increase (decrease) in income from continuing operations after income taxes.

No definition available.

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Change in accounting estimate financial effect increase (decrease) in income from continuing operations before income taxes.

No definition available.

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Gross favorable program profit adjustments.

No definition available.

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Gross unfavorable program profit adjustments.

No definition available.

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Represents the gross unfavorable program profit adjustments related to the Tactical Armoured Patrol Vehicle program.

No definition available.

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Represents the number of Tactical Armoured Patrol Vehicles (TAPV) under contract to be delivered to a Canadian customer.

No definition available.

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No definition available.

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