Annual report pursuant to Section 13 and 15(d)

Income Taxes - Additional Information (Detail)

v2.4.1.9
Income Taxes - Additional Information (Detail) (USD $)
12 Months Ended 6 Months Ended 12 Months Ended
Dec. 31, 2014
Dec. 31, 2014
Jun. 29, 2014
Dec. 31, 2013
Dec. 31, 2012
Income Tax Contingency [Line Items]          
Deferred tax assets, operating loss carryforwards $ 377,000us-gaap_DeferredTaxAssetsOperatingLossCarryforwards $ 377,000us-gaap_DeferredTaxAssetsOperatingLossCarryforwards      
Income tax examination, description As of December 31, 2014, with a few exceptions, the Company is no longer subject to U.S. federal, state, and foreign tax examinations by tax authorities for the tax years prior to 2011.        
Paulin [Member]          
Income Tax Contingency [Line Items]          
Valuation allowance 194,000us-gaap_OperatingLossCarryforwardsValuationAllowance
/ us-gaap_BusinessAcquisitionAxis
= hlm_PaulinMember
194,000us-gaap_OperatingLossCarryforwardsValuationAllowance
/ us-gaap_BusinessAcquisitionAxis
= hlm_PaulinMember
     
Increase in valuation allowance for net operating loss carryforwards 74,000us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount
/ us-gaap_BusinessAcquisitionAxis
= hlm_PaulinMember
       
General Business Tax Credit Carryforwards [Member]          
Income Tax Contingency [Line Items]          
Tax credit carryforwards 294,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_GeneralBusinessMember
294,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_GeneralBusinessMember
     
Valuation allowance 149,000us-gaap_TaxCreditCarryforwardValuationAllowance
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_GeneralBusinessMember
149,000us-gaap_TaxCreditCarryforwardValuationAllowance
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_GeneralBusinessMember
     
Foreign Tax Credit Carryforwards [Member]          
Income Tax Contingency [Line Items]          
Tax credit carryforwards 675,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_TaxCreditCarryforwardAxis
= hlm_ForeignTaxCreditCarryforwardsMember
675,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_TaxCreditCarryforwardAxis
= hlm_ForeignTaxCreditCarryforwardsMember
     
Successor [Member]          
Income Tax Contingency [Line Items]          
Decrease in the reserve for unrecognized tax benefits   30,000us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions
/ us-gaap_StatementScenarioAxis
= us-gaap_SuccessorMember
     
Reduction in deferred tax asset due to unrecognized tax benefit   (58,000)hlm_IncreaseDecreaseInDeferredTaxAssets
/ us-gaap_StatementScenarioAxis
= us-gaap_SuccessorMember
     
Predecessor [Member]          
Income Tax Contingency [Line Items]          
Decrease in the reserve for unrecognized tax benefits     1,559,000us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
1,538,000us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
1,438,000us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
Minimum [Member] | General Business Tax Credit Carryforwards [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2016        
Minimum [Member] | Foreign Tax Credit Carryforwards [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2020        
Maximum [Member] | General Business Tax Credit Carryforwards [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2033        
Maximum [Member] | Foreign Tax Credit Carryforwards [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2024        
State and Local Jurisdiction [Member]          
Income Tax Contingency [Line Items]          
Aggregate tax benefit 4,089,000us-gaap_TaxCreditCarryforwardDeferredTaxAsset
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
4,089,000us-gaap_TaxCreditCarryforwardDeferredTaxAsset
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
     
Valuation allowance 290,000us-gaap_OperatingLossCarryforwardsValuationAllowance
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
290,000us-gaap_OperatingLossCarryforwardsValuationAllowance
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
     
Increase in valuation allowance for net operating loss carryforwards 72,000us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
       
State and Local Jurisdiction [Member] | Minimum [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2015        
State and Local Jurisdiction [Member] | Maximum [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2034        
Domestic Tax Authority [Member]          
Income Tax Contingency [Line Items]          
Net operating loss carryforwards for tax 105,867,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
105,867,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
     
Valuation allowance 6,000us-gaap_DeferredTaxAssetsValuationAllowance
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
6,000us-gaap_DeferredTaxAssetsValuationAllowance
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
     
Decrease in net capital loss carryforward       374,000hlm_ChangeInCapitalLossValuationAllowance
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
 
Domestic Tax Authority [Member] | Minimum [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2022        
Domestic Tax Authority [Member] | Maximum [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2034        
Foreign Subsidiaries [Member]          
Income Tax Contingency [Line Items]          
Net operating loss carryforwards for tax 1,668,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= hlm_ForeignSubsidiariesMember
1,668,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= hlm_ForeignSubsidiariesMember
     
Valuation allowance 703,000us-gaap_DeferredTaxAssetsValuationAllowance
/ us-gaap_IncomeTaxAuthorityAxis
= hlm_ForeignSubsidiariesMember
703,000us-gaap_DeferredTaxAssetsValuationAllowance
/ us-gaap_IncomeTaxAuthorityAxis
= hlm_ForeignSubsidiariesMember
     
Deferred tax asset 312,000us-gaap_DeferredTaxAssetsGross
/ us-gaap_IncomeTaxAuthorityAxis
= hlm_ForeignSubsidiariesMember
312,000us-gaap_DeferredTaxAssetsGross
/ us-gaap_IncomeTaxAuthorityAxis
= hlm_ForeignSubsidiariesMember
     
Foreign Subsidiaries [Member] | Minimum [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2031        
Foreign Subsidiaries [Member] | Maximum [Member]          
Income Tax Contingency [Line Items]          
Expiry period of carryforwards 2034        
Luxembourg's Tax Codes [Member]          
Income Tax Contingency [Line Items]          
Indefinite operating loss carry forwards $ 1,300,000hlm_IndefiniteOperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= hlm_LuxembourgsTaxCodesMember