Subsidiary Guarantors Narrative (Details)	6 Months Ended
Jun. 30, 2021
Subsidiary Guarantors [Abstract]
Parent ownership percentage of subsidiary guarantors	100.00%

Parent's direct and indirect ownership percentage of each subsidiary Guarantor.

No definition available.

Name:	hii_Parentownershippercentageofsubsidiaryguarantors
Namespace Prefix:	hii_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration