Revenue - Revenue by Contract Type (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 02, 2017	Apr. 03, 2016
Revenue [Line Items]
Reimbursement Revenue	$ 2,018	$ 2,065
Revenues	7,441	7,476
Aerospace
Revenue [Line Items]
Reimbursement Revenue	0	0
Revenues	2,074	1,781
Combat Systems
Revenue [Line Items]
Reimbursement Revenue	207	216
Revenues	1,287	1,245
Information Systems and Technology
Revenue [Line Items]
Reimbursement Revenue	1,010	1,049
Revenues	2,146	2,328
Marine Systems
Revenue [Line Items]
Reimbursement Revenue	801	800
Revenues	1,934	2,122
Fixed-price Contract
Revenue [Line Items]
Revenues	5,035	5,063
Fixed-price Contract \| Aerospace
Revenue [Line Items]
Revenues	1,902	1,641
Fixed-price Contract \| Combat Systems
Revenue [Line Items]
Revenues	1,073	1,024
Fixed-price Contract \| Information Systems and Technology
Revenue [Line Items]
Revenues	930	1,077
Fixed-price Contract \| Marine Systems
Revenue [Line Items]
Revenues	1,130	1,321
Time-and-materials Contract
Revenue [Line Items]
Revenues	388	348
Time-and-materials Contract \| Aerospace
Revenue [Line Items]
Revenues	172	140
Time-and-materials Contract \| Combat Systems
Revenue [Line Items]
Revenues	7	5
Time-and-materials Contract \| Information Systems and Technology
Revenue [Line Items]
Revenues	206	202
Time-and-materials Contract \| Marine Systems
Revenue [Line Items]
Revenues	$ 3	$ 1

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.

No definition available.

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- Definition

Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

+ 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 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 45
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=68075638&loc=d3e60722-111653

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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