Contracts in Process (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 24, 2016	Jun. 30, 2017	Jun. 24, 2016	Dec. 31, 2016
Contracts Receivable [Abstract]
Unbilled contract receivables, gross	$ 1,930		$ 1,930		$ 2,020
Unliquidated progress payments	(720)		(720)		(827)
Unbilled contract receivables, net	1,210		1,210		1,193
Inventoried contract costs, gross	1,113		1,113		1,065
Unliquidated progress payments	(123)		(123)		(203)
Inventoried contract costs, net	990		990		862
Total contracts in process	2,200		2,200		$ 2,055
Summary of Inventory for Long Term Contracts or Programs [Roll Forward]
Amounts included in inventoried contract costs at beginning of the period	178	$ 157	173	$ 137
Contract costs incurred [Abstract]
IRAD and B&P	79	72	157	137
Other G&A	230	216	452	410
Total	309	288	609	547
Amounts charged to cost of sales	(313)	(282)	(608)	(521)
Amounts included in inventoried contract costs at end of the period	174	163	174	163
Operating Expenses [Abstract]
Selling, general and administrative expenses	63	59	134	111
Research and development expenses	17	13	32	24
Total	$ 80	$ 72	$ 166	$ 135

Amounts charged to cost of sales.

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The amount of costs incurred under contract costs during the period.

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The amount of general and administrative costs included in inventoried contract costs.

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The amount of general & administrative, independent research & development and bid & proposal costs included in inventoried contract costs.

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Refers to the amount of Independent research and development and bid and proposal costs included in inventoried contract costs.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount before progress payments for unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be gross amounts associated with contracts or programs where the recognized revenue for performance there under exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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Amount of advances received from customers under long-term contracts which have been offset against Unbilled Contract Receivables at the balance sheet date.

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Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings.

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Amount before valuation and LIFO reserves, and progress payments, of inventory associated with long-term contracts, expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount, after deduction of valuation reserves, other allowances, and customer advances received on long-term contracts or programs, of inventory expected to be converted to cash, sold or exchanged within the normal operating cycle.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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Amount of advances received from customers under long-term contracts which have been offset against inventories accounts at the balance sheet date.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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