Commercial Paper, Maximum Borrowing Capacity

No definition available.

Name:	noc_CommercialPaperMaximumBorrowingCapacity
Namespace Prefix:	noc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of cash paid for interest on money borrowed, including capitalized interest , net of interest received on loans and other debt instruments during the current period.

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentsAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Identification of whether the entity has been in compliance with any credit facility debt covenants during the period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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+ Details

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

- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

+ References

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: 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(19)(a))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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+ Details

Name:	us-gaap_ShortTermBorrowings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentAxis=noc_FiveYearTermMemberDomain
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=noc_TwoYearTermMemberDomain
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=noc_TwoThousandThirtyMember
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=noc_TwoThousandFortyMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=noc_TwoThousandFiftyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_CommercialPaperMember
Namespace Prefix:
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Balance Type:
Period Type:

Amounts in Paragraphs - Debt (Details 3) £ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2020 GBP (£)	Dec. 01, 2020 USD ($)	Dec. 01, 2020 GBP (£)	Mar. 23, 2020 USD ($) Rate
Debt Instrument [Line Items]
Credit Facility, Covenant Terms, Maximum Debt to Capitalization Ratio	The company also cannot permit the ratio of its debt to capitalization (as set forth in the credit agreements) to exceed 65 percent.
Line of Credit Facility, Covenant Compliance	the company was in compliance with all covenants under its credit agreements.
Long-term Debt, Fair Value	$ 18,200	$ 15,100
Interest paid, net of interest received	572	521	$ 456
Five Year Term [Member] [Domain]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	2,000
Credit facilities	0
Two Year Term [Member] [Domain]
Debt Instrument [Line Items]
Credit facilities	$ 0	$ 78			$ 68	£ 50
Debt Instruments [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	1.89%			1.89%
Two Thousand Thirty
Debt Instruments [Abstract]
Debt Instrument, Face Amount							$ 750
Debt Instrument, Interest Rate, Stated Percentage	4.40%			4.40%			4.40%
Two Thousand Forty [Member]
Debt Instruments [Abstract]
Debt Instrument, Face Amount							$ 500
Debt Instrument, Interest Rate, Stated Percentage \| Rate							5.15%
Two Thousand Fifty
Debt Instruments [Abstract]
Debt Instrument, Face Amount							$ 1,000
Debt Instrument, Interest Rate, Stated Percentage	5.25%			5.25%			5.25%
Revolving Credit Facility [Member] \| Two Year Term [Member] [Domain]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 163			£ 120
Commercial Paper [Member]
Debt Instrument [Line Items]
Commercial Paper, Maximum Borrowing Capacity	2,000
Short-term Debt	$ 0