DESCRIPTION OF THE PLAN (Details) - EBP 310 $ in Thousands	12 Months Ended
Dec. 31, 2025 USD ($) yr loan	Dec. 31, 2024 USD ($)
EBP, Description of Plan [Line Items]
Requisite age for participation \| yr	18
Participant contribution, automatic, deferral rate	3.00%
Participant contribution, automatic, annual increase deferral rate	1.00%
Employer contribution maximum vesting age \| yr	65
Nonvested account, break in service forfeiture period	5 years
Forfeited nonvested account	$ 109	$ 52
Forfeited nonvested account, decrease from employer contribution	$ 510
Investment contribution, maximum tax deferred compensation deposit, percent	4.00%
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
Involuntary cash-out limit	$ 7
Participant contribution, minimum percentage of annual compensation to total compensation to achieve maximum retirement benefit	4.00%
Participant contribution, minimum percentage of pay cap limit to achieve maximum retirement benefit	4.00%
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	10.70%
EBP, FSSP Retirement Account Contribution
EBP, Description of Plan [Line Items]
Participant contribution, pretax, minimum annual compensation to total compensation, percentage	1.00%
Participant contribution, pretax, maximum annual compensation to total compensation, percentage	4.00%
EBP, FSSP Savings Account Contribution
EBP, Description of Plan [Line Items]
Participant contribution, pretax, minimum annual compensation to total compensation, percentage	1.00%
Participant contribution, pretax, maximum annual compensation to total compensation, percentage	75.00%
Employer contribution, matching percentage	50.00%
Employer contribution, participant compensation matched, percentage	4.00%
EBP, Employer Contribution Vesting, Tranche One
EBP, Description of Plan [Line Items]
Employer contribution vesting percentage	50.00%
Employer contribution vesting service period	2 years
EBP, Employer Contribution Vesting, Tranche Two
EBP, Description of Plan [Line Items]
Employer contribution vesting percentage	100.00%
Employer contribution vesting service period	3 years

EBP, Employer Contribution Maximum Vesting Age

No definition available.

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

- Definition

EBP, Employer Contribution Vesting Percentage

+ References

No definition available.

+ Details

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

- Definition

EBP, Employer Contribution Vesting Service Period

+ References

No definition available.

+ Details

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

- Definition

EBP, Investment Contribution, Maximum Tax Deferred Compensation Deposit, Percent

+ References

No definition available.

+ Details

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

- Definition

EBP, Investment Contribution, Minimum Increment, Percent

+ References

No definition available.

+ Details

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

- Definition

EBP, Involuntary Cash-out Limit

+ References

No definition available.

+ Details

Name:	hii_EBPInvoluntaryCashOutLimit
Namespace Prefix:	hii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

EBP, Involuntary Cash-out Limit, Maximum Age

+ References

No definition available.

+ Details

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

- Definition

EBP, Nonvested Account, Break In Service Forfeiture Period

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

Name:	hii_EBPNoteReceivableFromParticipantAccountPrimaryResidenceMaximumBorrowingTerm
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

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

- Definition

EBP, Participant Contribution, Minimum Percentage Of Annual Compensation To Total Compensation To Achieve Maximum Retirement Benefit

+ References

No definition available.

+ Details

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

- Definition

EBP, Participant Contribution, Minimum Percentage Of Pay Cap Limit To Achieve Maximum Retirement Benefit

+ References

No definition available.

+ Details

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

- Definition

EBP, Participant Contribution, Pretax, Minimum Annual Compensation to Total Compensation, Percentage

+ References

No definition available.

+ Details

Name:	hii_EBPParticipantContributionPretaxMinimumAnnualCompensationToTotalCompensationPercentage
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

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

Name:	us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems
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

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

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
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

Name:	us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccountDecreaseForEmployerContribution
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

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage
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

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMinimumBorrowingAmount
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

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage
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_EBP310Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	hii_EBPEmployeeContributionTypeAxis=hii_EBPFSSPRetirementAccountContributionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	hii_EBPEmployeeContributionTypeAxis=hii_EBPFSSPSavingsAccountContributionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	hii_EBPEmployerContributionVestingAxis=hii_EBPEmployerContributionVestingTrancheOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	hii_EBPEmployerContributionVestingAxis=hii_EBPEmployerContributionVestingTrancheTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: