DESCRIPTION OF THE PLAN - Narrative (Details) - EBP 011 $ in Thousands	12 Months Ended
Dec. 31, 2025 USD ($) withdrawal loan yr	Dec. 31, 2024 USD ($)
EBP, Description of Plan [Line Items]
Requisite age for participation \| yr	18
Transfers of plan assets in due to merger	$ 81,471
Vesting percentage	100.00%
Minimum annual compensation to total compensation, percentage	1.00%
Maximum annual compensation to total compensation, percentage	75.00%
Participant contribution, minimum increment, percent	1.00%
Participant contribution, automatic, deferral rate	2.00%
Participant contribution, automatic, enrollment period following date of hire	45 days
Participant contribution, automatic, annual increase deferral rate	1.00%
Vesting period	3 years
Forfeited nonvested account	$ 1,743	$ 73
Forfeited nonvested account, decrease from employer contribution	$ 5,362
Investment contribution, minimum increment, percent	1.00%
Note receivable from participant, account, minimum borrowing, amount	$ 1
Note receivable from participant, account, maximum borrowing, amount	$ 50
Note receivable from participant, account, time period for loans used to reduce maximum borrowing amount	12 months
Note receivable from participant, account, maximum borrowing, to total account, percentage	50.00%
Note receivable from participant, maximum number of loans outstanding \| loan	1
Participant loan, basis spread on variable rate	1.00%
Note receivable from participant, general loan, maximum borrowing term	5 years
Note receivable from participant, account, primary residence, maximum borrowing term	15 years
Note receivable from participant, loans transferred in from plan merger, borrowing term (greater than)	15 years
Involuntary cash-out limit, maximum age \| yr	73
Maximum number of after-tax contribution withdrawals per quarter \| withdrawal	1
Maximum number of company matching contribution withdrawals per quarter \| withdrawal	1
Minimum
EBP, Description of Plan [Line Items]
Asset held for investment, participant loan, interest rate	4.25%
Maximum
EBP, Description of Plan [Line Items]
Asset held for investment, participant loan, interest rate	9.50%

EBP, Employer Contribution Vesting Percentage

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

EBP, Employer Contribution Vesting Service Period

+ References

No definition available.

+ Details

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

- Definition

EBP, Investment Contribution, Minimum Increment, Percent

+ References

No definition available.

+ Details

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Namespace Prefix:	hii_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Involuntary Cash-out Limit, Maximum Age

+ References

No definition available.

+ Details

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

- Definition

EBP, Maximum Number Of After-Tax Contribution Withdrawals Per Quarter

+ References

No definition available.

+ Details

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

- Definition

EBP, Maximum Number Of Company Matching Contribution Withdrawals Per Quarter

+ References

No definition available.

+ Details

Name:	hii_EBPMaximumNumberOfCompanyMatchingContributionWithdrawalsPerQuarter
Namespace Prefix:	hii_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, Account, Primary Residence, Maximum Borrowing Term

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

Name:	hii_EBPNoteReceivableFromParticipantAccountTimePeriodForLoansUsedToReduceMaximumBorrowingAmount
Namespace Prefix:	hii_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term

+ References

No definition available.

+ Details

Name:	hii_EBPNoteReceivableFromParticipantGeneralLoanMaximumBorrowingTerm
Namespace Prefix:	hii_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, Loans Transferred In From Plan Merger, Borrowing Term

+ References

No definition available.

+ Details

Name:	hii_EBPNoteReceivableFromParticipantLoansTransferredInFromPlanMergerBorrowingTerm
Namespace Prefix:	hii_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, Maximum Number Of Loans Outstanding

+ References

No definition available.

+ Details

Name:	hii_EBPNoteReceivableFromParticipantMaximumNumberOfLoansOutstanding
Namespace Prefix:	hii_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Annual Increase Deferral Rate

+ References

No definition available.

+ Details

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Namespace Prefix:	hii_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Enrollment Period Following Date Of Hire

+ References

No definition available.

+ Details

Name:	hii_EBPParticipantContributionAutomaticEnrollmentPeriodFollowingDateOfHire
Namespace Prefix:	hii_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Maximum Contribution to Eligible Compensation, Percentage

+ References

No definition available.

+ Details

Name:	hii_EBPParticipantContributionMaximumContributionToEligibleCompensationPercentage
Namespace Prefix:	hii_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Minimum Contribution to Eligible Compensation, Percentage

+ References

No definition available.

+ Details

Name:	hii_EBPParticipantContributionMinimumContributionToEligibleCompensationPercentage
Namespace Prefix:	hii_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Minimum Increment, Percent

+ References

No definition available.

+ Details

Name:	hii_EBPParticipantContributionMinimumIncrementPercent
Namespace Prefix:	hii_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Loan, Basis Spread On Variable Rate

+ References

No definition available.

+ Details

Name:	hii_EBPParticipantLoanBasisSpreadOnVariableRate
Namespace Prefix:	hii_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Requisite Age For Participation

+ References

No definition available.

+ Details

Name:	hii_EBPRequisiteAgeForParticipation
Namespace Prefix:	hii_
Data Type:	xbrli:integerItemType
Balance Type:	na
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

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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

- Definition

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from employer contribution.

+ 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/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount
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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Namespace Prefix:	us-gaap-ebp_
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

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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

- Details

Name:	dei_LegalEntityAxis=hii_EBP011Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

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