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Employee Benefit Plans - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2015
Defined Benefit Pension Plans  
Defined Benefit Plan Disclosure [Line Items]  
Expected contribution $ 19.6vhi_DefinedBenefitPlanEstimatedEmployerContributionsInCurrentFiscalYear
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
OPEB  
Defined Benefit Plan Disclosure [Line Items]  
Expected contribution $ 1.3vhi_DefinedBenefitPlanEstimatedEmployerContributionsInCurrentFiscalYear
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember