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Loans secured by one to four-family residential property of the borrower are generally referred to as residential mortgage loans. Repayment terms for residential mortgage loans may vary considerably. Such loans may be structured to provide for full amortization of principal, partial amortization with a balloon payment at a specified date, or negative amortization. Interest rates may be fixed or variable. This item excludes subordinated loans such as home equity lines of credit.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 8 -Paragraph 40, 41 -IssueDate 2006-05-01 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 13 -Subparagraph e Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph a, b -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 8 -Subparagraph c(i) -Subsection I truefalseTotal loans6false0us-gaap_MortgageLoansOnRealEstatePrincipalAmountOfDelinquentLoansus-gaaptruedebitinstantNo definition 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Loans secured by one to four-family residential property of the borrower are generally referred to as residential mortgage loans. Repayment terms for residential mortgage loans may vary considerably. Such loans may be structured to provide for full amortization of principal, partial amortization with a balloon payment at a specified date, or negative amortization. Interest rates may be fixed or variable. 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Loans secured by one to four-family residential property of the borrower are generally referred to as residential mortgage loans. Repayment terms for residential mortgage loans may vary considerably. Such loans may be structured to provide for full amortization of principal, partial amortization with a balloon payment at a specified date, or negative amortization. Interest rates may be fixed or variable. This item excludes subordinated loans such as home equity lines of credit.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 8 -Paragraph 40, 41 -IssueDate 2006-05-01 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 13 -Subparagraph e Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph a, b -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 8 -Subparagraph c(i) -Subsection I truefalseTotal loans108false0us-gaap_MortgageLoansOnRealEstatePrincipalAmountOfDelinquentLoansus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of principal due on loans that have been delinquent, which may exclude loans having interest delinquent for three months or less, as of the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule IV -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 29 -Article 12 falsefalse90 Days or more accruing109false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://hcsbonline.com/role/loansandallowanceforloanlossesdetailstwo1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse61falsefalseUSDtruefalse{us-gaap_MortgageLoansOnRealEstateLoanTypeAxis} : Home equity credit lines [Member] 3/31/2011 USD ($) $BalanceAsOf_31Mar2011_Home_Equity_Memberhttp://www.sec.gov/CIK0000921847instant2011-03-31T00:00:000001-01-01T00:00:00falsefalseHome equity credit lines [Member]us-gaap_MortgageLoansOnRealEstateLoanTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_HomeEquityMemberus-gaap_MortgageLoansOnRealEstateLoanTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$62falsefalseUSDtruefalse{us-gaap_MortgageLoansOnRealEstateLoanTypeAxis} : Home equity credit lines [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Home_Equity_Memberhttp://www.sec.gov/CIK0000921847instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseHome equity credit lines [Member]us-gaap_MortgageLoansOnRealEstateLoanTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_HomeEquityMemberus-gaap_MortgageLoansOnRealEstateLoanTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseHome equity credit lines [Member]110true0hcbk_ComparisonOfDelinquentLoansByClassAbstracthcbkfalsenadurationComparison Of Delinquent Loans By Class Abstract.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringComparison Of Delinquent Loans By Class Abstract.falsefalseComparison of delinquent loans by class111false0hcbk_LoansAndLeasesReceivableConsumerMortgagePastDueTotalhcbkfalsedebitinstantLoans And Leases Receivable Consumer Mortgage Past Due Total.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse53160005316falsefalsefalsefalsefalse2truefalsefalse54780005478falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLoans And Leases Receivable Consumer Mortgage Past Due Total.No authoritative reference available.truefalseTotal Past Due112false0hcbk_LoansAndLeasesReceivableConsumerMortgageCurrenthcbkfalsedebitinstantLoans And Leases Receivable Consumer Mortgage Current.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse130932000130932falsefalsefalsefalsefalse2truefalsefalse131989000131989falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLoans And Leases Receivable Consumer Mortgage Current.No authoritative reference available.truefalseCurrent Loans113false0us-gaap_LoansAndLeasesReceivableConsumerMortgageus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse136248000136248falsefalsefalsefalsefalse2truefalsefalse137467000137467falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryReflects the gross carrying amount of unpaid loans issued to individuals to acquire or improve land or a building or to provide cash to the borrower, and which are secured by the acquired or improved realty. Loans secured by one to four-family residential property of the borrower are generally referred to as residential mortgage loans. Repayment terms for residential mortgage loans may vary considerably. Such loans may be structured to provide for full amortization of principal, partial amortization with a balloon payment at a specified date, or negative amortization. Interest rates may be fixed or variable. This item excludes subordinated loans such as home equity lines of credit.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 8 -Paragraph 40, 41 -IssueDate 2006-05-01 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 13 -Subparagraph e Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph a, b -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 8 -Subparagraph c(i) -Subsection I truefalseTotal loans114false0us-gaap_MortgageLoansOnRealEstatePrincipalAmountOfDelinquentLoansus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of principal due on loans that have been delinquent, which may exclude loans having interest delinquent for three months or less, as of the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule IV -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 29 -Article 12 falsefalse90 Days or more accruing115false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://hcsbonline.com/role/loansandallowanceforloanlossesdetailstwo1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse63falsefalseUSDtruefalse{us-gaap_MortgageLoansOnRealEstateLoanTypeAxis} : Other Loan [Member] 3/31/2011 USD ($) $BalanceAsOf_31Mar2011_Other_Loan_Memberhttp://www.sec.gov/CIK0000921847instant2011-03-31T00:00:000001-01-01T00:00:00falsefalseOther [Member]us-gaap_MortgageLoansOnRealEstateLoanTypeAxisxbrldihttp://xbrl.org/2006/xbrldihcbk_OtherLoanMemberus-gaap_MortgageLoansOnRealEstateLoanTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$64falsefalseUSDtruefalse{us-gaap_MortgageLoansOnRealEstateLoanTypeAxis} : Other Loan [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Other_Loan_Memberhttp://www.sec.gov/CIK0000921847instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseOther [Member]us-gaap_MortgageLoansOnRealEstateLoanTypeAxisxbrldihttp://xbrl.org/2006/xbrldihcbk_OtherLoanMemberus-gaap_MortgageLoansOnRealEstateLoanTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseOther [Member]116true0hcbk_ComparisonOfDelinquentLoansByClassAbstracthcbkfalsenadurationComparison Of Delinquent Loans By Class Abstract.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringComparison Of Delinquent Loans By Class Abstract.falsefalseComparison of delinquent loans by class117false0hcbk_LoansAndLeasesReceivableConsumerMortgagePastDueTotalhcbkfalsedebitinstantLoans And Leases Receivable Consumer Mortgage Past Due Total.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse558000558falsefalsefalsefalsefalse2truefalsefalse28570002857falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLoans And Leases Receivable Consumer Mortgage Past Due Total.No authoritative reference available.truefalseTotal Past Due118false0hcbk_LoansAndLeasesReceivableConsumerMortgageCurrenthcbkfalsedebitinstantLoans And Leases Receivable Consumer Mortgage Current.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse1910300019103falsefalsefalsefalsefalse2truefalsefalse1640700016407falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLoans And Leases Receivable Consumer Mortgage Current.No authoritative reference available.truefalseCurrent Loans119false0us-gaap_LoansAndLeasesReceivableConsumerMortgageus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse1966100019661falsefalsefalsefalsefalse2truefalsefalse1926400019264falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryReflects the gross carrying amount of unpaid loans issued to individuals to acquire or improve land or a building or to provide cash to the borrower, and which are secured by the acquired or improved realty. Loans secured by one to four-family residential property of the borrower are generally referred to as residential mortgage loans. Repayment terms for residential mortgage loans may vary considerably. Such loans may be structured to provide for full amortization of principal, partial amortization with a balloon payment at a specified date, or negative amortization. Interest rates may be fixed or variable. This item excludes subordinated loans such as home equity lines of credit.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 8 -Paragraph 40, 41 -IssueDate 2006-05-01 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 13 -Subparagraph e Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph a, b -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 8 -Subparagraph c(i) -Subsection I truefalseTotal loans120false0us-gaap_MortgageLoansOnRealEstatePrincipalAmountOfDelinquentLoansus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsetruefalsefalsefalse2truefalsefalse00falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of principal due on loans that have been delinquent, which may exclude loans having interest delinquent for three months or less, as of the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule IV -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 29 -Article 12 falsefalse90 Days or more accruing2119Loans and Allowance for Loan Losses (Details 2) (USD $)ThousandsUnKnownUnKnownUnKnownfalsetrue