Unbilled Receivables, Net (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivable, net of progress and performance-based payments received	$ 5,180	$ 5,379
Allowance for expected credit losses	(40)	(45)
Unbilled receivables, net	5,140	5,334
US Government [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	19,315	17,347
Government Contract Receivable, Progress Payment Offset	14,615	12,838
Unbilled receivable, net of progress and performance-based payments received	4,700	4,509
International and Other Customers [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	3,361	4,063
Progress and performance-based payments received	(2,881)	(3,193)
Unbilled receivable, net of progress and performance-based payments received	$ 480	$ 870

Allowance for Expected Credit Losses Unbilled Receivables

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- Definition

Amount of progress payments offset against unbilled international and other contract receivables.

+ 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

No definition available.

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- Definition

Amount of progress payment offset against unbilled government contract receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 310
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84167097&loc=d3e55549-109407

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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=118261985&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=120391452&loc=d3e13212-122682

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

+ References

No definition available.

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