Unbilled Receivables, Net (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivable, net of progress and performance-based payments received	$ 5,065	$ 3,504
Allowance for doubtful accounts	(39)	(39)
Unbilled receivables, net	5,026	3,465
US Government [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	16,823	12,513
Progress and performance-based payments received	(12,539)	(9,447)
Unbilled receivable, net of progress and performance-based payments received	4,284	3,066
International and Other Customers [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	3,811	3,424
Progress and performance-based payments received	(3,030)	(2,986)
Unbilled receivable, net of progress and performance-based payments received	$ 781	$ 438

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- Definition

Unbilled Contract Receivable, Net

+ References

No definition available.

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- Definition

Unbilled Contract Receivable, net of progress and performance-based payments

+ References

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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

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- Definition

The amount of the offset related to government or other customer advances received on a contract when the expected advances will be applied in payment to those particular charges of the receivable.

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 310
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=68054760&loc=d3e55302-109406

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(c)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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