Annual report pursuant to Section 13 and 15(d)

Related Party Transactions - Additional Information (Detail)

v2.4.1.9
Related Party Transactions - Additional Information (Detail) (USD $)
In Thousands, unless otherwise specified
12 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended
Dec. 31, 2014
Property
Lease
Dec. 31, 2014
Jun. 29, 2014
Jun. 29, 2014
Dec. 31, 2013
Dec. 31, 2012
Paulin [Member]            
Capital Leased Assets [Line Items]            
Number of leases 3hlm_NumberOfLease
/ us-gaap_BusinessAcquisitionAxis
= hlm_PaulinMember
         
Number of properties leased 5hlm_NumberOfLeasedProperties
/ us-gaap_BusinessAcquisitionAxis
= hlm_PaulinMember
         
Lease agreement date Feb. 19, 2013          
Successor [Member]            
Capital Leased Assets [Line Items]            
Management and transaction fee charges and expenses to related party   $ 276us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
/ us-gaap_StatementScenarioAxis
= us-gaap_SuccessorMember
       
Rental expense for the leases   146us-gaap_LeaseAndRentalExpense
/ us-gaap_StatementScenarioAxis
= us-gaap_SuccessorMember
       
Successor [Member] | Paulin [Member]            
Capital Leased Assets [Line Items]            
Rental expense for the leases   371us-gaap_LeaseAndRentalExpense
/ us-gaap_BusinessAcquisitionAxis
= hlm_PaulinMember
/ us-gaap_StatementScenarioAxis
= us-gaap_SuccessorMember
       
Predecessor [Member]            
Capital Leased Assets [Line Items]            
Management and transaction fee charges and expenses to related party     15us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
15us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
77us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
155us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
Rental expense for the leases     165us-gaap_LeaseAndRentalExpense
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
  311us-gaap_LeaseAndRentalExpense
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
311us-gaap_LeaseAndRentalExpense
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
Predecessor [Member] | Paulin [Member]            
Capital Leased Assets [Line Items]            
Rental expense for the leases     $ 376us-gaap_LeaseAndRentalExpense
/ us-gaap_BusinessAcquisitionAxis
= hlm_PaulinMember
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember
  $ 687us-gaap_LeaseAndRentalExpense
/ us-gaap_BusinessAcquisitionAxis
= hlm_PaulinMember
/ us-gaap_StatementScenarioAxis
= us-gaap_PredecessorMember