Disposition of IT and Mission Support Services (Details 1) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Jan. 30, 2021
Income Statement, Balance Sheet and Additional Disclosures by Disposal Group
Disposal Group, Including Discontinued Operation, Consideration		$ 3,400
Pre-tax gain on sale of business	$ 2,000
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax	20
Revenue from Individually Significant Component Disposed of or Held-for-Sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax	$ 162

Pre-tax gain on sale of business

No definition available.

Name:	noc_PreTaxGainOnSaleOfBusiness
Namespace Prefix:	noc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Revenue from Individually Significant Component Disposed of or Held-for-Sale, Excluding Discontinued Operations, Attributable to Parent

+ References

No definition available.

+ Details

Name:	noc_RevenueFromIndividuallySignificantComponentDisposedOfOrHeldForSaleExcludingDiscontinuedOperationsAttributableToParentBeforeIncomeTax
Namespace Prefix:	noc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before tax of income (loss) from an individually significant component disposed of or held-for-sale attributable to parent. Excludes discontinued operations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-3A

+ Details

Name:	us-gaap_IncomeLossFromIndividuallySignificantComponentDisposedOfOrHeldForSaleExcludingDiscontinuedOperationsAttributableToParentBeforeIncomeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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.

+ Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration