Description of the Plan (Details) - EBP 018	12 Months Ended
Dec. 31, 2025 USD ($) h $ / h
EBP, Description of Plan [Line Items]
Transfers to other plan	$ 35,880,000
Initial transfer	500
Subsequent transfers	500
Minimum borrowing, amount	$ 500
Maximum borrowing, to total account, percentage	50.00%
Maximum borrowing, amount	$ 50,000
Time period for loans used to reduce maximum borrowing amount	12 months
Basis spread on variable rate	1.00%
Minimum
EBP, Description of Plan [Line Items]
Gross earnings (US dollars per hour) \| $ / h	0.75
Maximum
EBP, Description of Plan [Line Items]
Gross earnings (US dollars per hour) \| $ / h	2.00
Employer Matching Contribution
EBP, Description of Plan [Line Items]
Matching percentage	50.00%
Employer Matching Contribution, Sikorsky Participants
EBP, Description of Plan [Line Items]
Matching percentage	75.00%
Employer Matching Contribution, Nonelective Contribution
EBP, Description of Plan [Line Items]
Matching percentage	4.00%
Hours of service per week \| h	40
Hours of service per calendar year \| h	2,080

EBP, Hours Of Service Per Calendar Year

No definition available.

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Namespace Prefix:	lmt_
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Balance Type:	na
Period Type:	duration

- Definition

EBP, Hours Of Service Per Week

+ References

No definition available.

+ Details

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Namespace Prefix:	lmt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Nonelective Contribution, Gross Earnings

+ References

No definition available.

+ Details

Name:	lmt_EBPNonelectiveContributionGrossEarnings
Namespace Prefix:	lmt_
Data Type:	srt-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Definition

EBP, Note Receivable From Participant, Account, Time Period For Loans Used To Reduce Maximum Borrowing Amount

+ References

No definition available.

+ Details

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Namespace Prefix:	lmt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Loan, Basis Spread On Variable Rate

+ References

No definition available.

+ Details

Name:	lmt_EBPParticipantLoanBasisSpreadOnVariableRate
Namespace Prefix:	lmt_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Self-Directed Brokerage Account, Initial Transfer

+ References

No definition available.

+ Details

Name:	lmt_EBPSelfDirectedBrokerageAccountInitialTransfer
Namespace Prefix:	lmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

EBP, Self-Directed Brokerage Account, Subsequent Transfers

+ References

No definition available.

+ Details

Name:	lmt_EBPSelfDirectedBrokerageAccountSubsequentTransfers
Namespace Prefix:	lmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of net asset available for benefit transferred to (from) employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from (to) external plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule III))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 45
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477063/962-205-45-8

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:
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- Details

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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
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