v3.26.1
Income Taxes (Valuation Allowance) (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Income Tax Disclosure [Abstract]
Valuation Allowance Deductions
$ (82)
$ (88)
$ (28)
Valuation Allowance Additions
$ 35
$ 20
$ 13
X
- Definition
Valuation Allowance Additions
+ References
No definition available.
+ Details
Name:
nvl_ValuationAllowanceAdditions
Namespace Prefix:
nvl_
Data Type:
xbrli:monetaryItemType
Balance Type:
credit
Period Type:
instant
X
- Definition
Valuation Allowance Deductions
+ References
No definition available.
+ Details
Name:
nvl_ValuationAllowanceDeductions
Namespace Prefix:
nvl_
Data Type:
xbrli:monetaryItemType
Balance Type:
debit
Period Type:
instant
X
- References
No definition available.
+ Details
Name:
us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix:
us-gaap_
Data Type:
xbrli:stringItemType
Balance Type:
na
Period Type:
duration