Unbilled Receivables (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Contracts In Process [Line Items]
Unbilled revenue	$ 30,497	$ 27,908
Advances and progress billings	(23,130)	(21,332)
Net unbilled receivables	7,367	$ 6,576
Combat Systems
Contracts In Process [Line Items]
Net unbilled receivables	$ 2,200

Contracts In Process [Line Items]

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 210
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68069949&loc=d3e52987-109388

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 210
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68071014&loc=d3e53318-109389

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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- Definition

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.

+ Details

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