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Such securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income, a separate component of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13, 137 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 16 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 22 false 4 Available-for-sale Securities, Equity Securities 2 us-gaap_AvailableForSaleSecuritiesEquitySecurities us-gaap true debit instant No definition available. false false false false false false false false false false false label false 1 false true false false 7314000 7314000 false false false 2 false false false false 0 0 false false false 3 false true false false 7075000 7075000 false false false xbrli:monetaryItemType monetary For an unclassified balance sheet, this item represents equity securities categorized neither as held-to-maturity nor trading. Equity securities represent ownership interests or the right to acquire ownership interests in corporations and other legal entities which ownership interest is represented by shares of common or preferred stock (which is not mandatorily redeemable or redeemable at the option of the holder), convertible securities, stock rights, or stock warrants. Unrealized gains and losses related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 22 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 19 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 86-40 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 16 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 3 -Subparagraph c false 5 Available-for-sale Securities 2 us-gaap_AvailableForSaleSecurities us-gaap true debit instant No definition available. false false false false false false false false false false false label false 1 false true false false 15052238000 15052238000 false false false 2 false false false false 0 0 false false false 3 false true false false 12211771000 12211771000 false false false xbrli:monetaryItemType monetary For an unclassified balance sheet, this item represents investments in debt and equity securities which are categorized neither as held-to-maturity nor trading. Such securities are reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 16 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 22 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 14 false 6 Available-for-Sale Securities (Textuals) [Abstract] 2 hcbk_AvailableForSaleSecuritiesTextualsAbstract hcbk false na duration Available for Sale Securities. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false xbrli:stringItemType string Available for Sale Securities. false 7 Available-for-sale Securities, Equity Securities 2 us-gaap_AvailableForSaleSecuritiesEquitySecurities us-gaap true debit instant No definition available. false false false false false false false false false false false label false 1 false true false false 7314000 7314000 false false false 2 false false false false 0 0 false false false 3 false true false false 7075000 7075000 false false false xbrli:monetaryItemType monetary For an unclassified balance sheet, this item represents equity securities categorized neither as held-to-maturity nor trading. Equity securities represent ownership interests or the right to acquire ownership interests in corporations and other legal entities which ownership interest is represented by shares of common or preferred stock (which is not mandatorily redeemable or redeemable at the option of the holder), convertible securities, stock rights, or stock warrants. Unrealized gains and losses related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 22 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 19 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 86-40 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 16 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 3 -Subparagraph c false 8 Fair Value Assets Measured on Nonrecurring Basis Financial Statement Captions [Line Items] 2 us-gaap_FairValueAssetsMeasuredOnNonrecurringBasisFinancialStatementCaptionsLineItems us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false xbrli:stringItemType string Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. false 9 Impaired Loans 2 hcbk_ImpairedLoansFairValueDisclosure hcbk false debit instant Impaired Loans Fair Value Disclosure. false false false false false false false false false false false verboselabel false 1 false true false false 11500000 11500000 false false false 2 false false false false 0 0 false false false 3 false true false false 11200000 11200000 false false false xbrli:monetaryItemType monetary Impaired Loans Fair Value Disclosure. No authoritative reference available. false 10 Foreclosed Real Estate 2 hcbk_ForeclosedRealEstateFairValueDisclosure hcbk false debit instant Foreclosed Real Estate, Fair Value Disclosure. false false false false false false false false false false false verboselabel false 1 false true false false 40300000 40300000 false false false 2 false false false false 0 0 false false false 3 false true false false 16700000 16700000 false false false xbrli:monetaryItemType monetary Foreclosed Real Estate, Fair Value Disclosure. No authoritative reference available. false 11 Allowance for Loan Losses Related to Commercial and Construction Loans 2 hcbk_AllowanceForLoanLossesRelatedToCommercialAndConstructionLoans hcbk false debit instant Allowance for loan losses related to non-performing commercial and construction loans. false false false false false false false false false false false verboselabel false 1 false true false false 2700000 2700000 false false false 2 false false false false 0 0 false false false 3 false true false false 2100000 2100000 false false false xbrli:monetaryItemType monetary Allowance for loan losses related to non-performing commercial and construction loans. No authoritative reference available. false 12 Fair Value Assets Measured On Nonrecurring Basis Financial Statement Captions (Textuals) [Abstract] 2 hcbk_FairValueAssetsMeasuredOnNonrecurringBasisFinancialStatementCaptionsTextualsAbstract hcbk false na duration Fair Value Assets Measured On Nonrecurring Basis Financial Statement Captions (Textuals) [Abstract] false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false xbrli:stringItemType string Fair Value Assets Measured On Nonrecurring Basis Financial Statement Captions (Textuals) [Abstract] false 13 Impaired Loans 2 hcbk_ImpairedLoansFairValueDisclosure hcbk false debit instant Impaired Loans Fair Value Disclosure. false false false false false false false false false false false verboselabel false 1 false true false false 11500000 11500000 false false false 2 false false false false 0 0 false false false 3 false true false false 11200000 11200000 false false false xbrli:monetaryItemType monetary Impaired Loans Fair Value Disclosure. No authoritative reference available. false 14 Foreclosed Real Estate 2 hcbk_ForeclosedRealEstateFairValueDisclosure hcbk false debit instant Foreclosed Real Estate, Fair Value Disclosure. false false false false false false false false false false false verboselabel false 1 false true false false 40300000 40300000 false false false 2 false false false false 0 0 false false false 3 false true false false 16700000 16700000 false false false xbrli:monetaryItemType monetary Foreclosed Real Estate, Fair Value Disclosure. No authoritative reference available. false 15 Provision for loan losses related to commercial and construction loans 2 hcbk_ProvisionForLoanLossesRelatedToCommercialAndConstructionLoans hcbk false debit duration Provision for loan losses related to commercial and construction loans. false false false false false false false false false false false verboselabel false 1 false true false false 579000 579000 false false false 2 false true false false 1300000 1300000 false false false 3 false false false false 0 0 false false false xbrli:monetaryItemType monetary Provision for loan losses related to commercial and construction loans. No authoritative reference available. false 16 Allowance for Loan and Lease Losses, Write-offs 2 us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 4100000 4100000 false false false 2 false true false false 2900000 2900000 false false false 3 false false false false 0 0 false false false xbrli:monetaryItemType monetary Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 20 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 false 17 Write Downs and Net Loss on Sale Foreclosed Real Estate 2 hcbk_WriteDownsAndNetLossOnSaleForeclosedRealEstate hcbk false debit duration Write downs and net loss on sale related to foreclosed real estate that were charged to non-interest expense. false false false false false false false false false false false verboselabel false 1 false true false false 1200000 1200000 false false false 2 false true false false 2000000 2000000 false false false 3 false false false false 0 0 false false false xbrli:monetaryItemType monetary Write downs and net loss on sale related to foreclosed real estate that were charged to non-interest expense. No authoritative reference available. false 18 Carrying Amount of financial instruments, Assets: 2 us-gaap_AssetsAbstract us-gaap true na duration No definition available. false false false false false true false false false false false terselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 19 Cash and due from banks 2 us-gaap_CashAndDueFromBanks us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 147614000 147614000 false false false 2 false false false false 0 0 false false false 3 false true false false 198752000 198752000 false false false xbrli:monetaryItemType monetary For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 6 -Paragraph 1, 2, 3, 7, 11 -IssueDate 2006-05-01 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1, 2, 3 -Article 9 false 20 Federal funds sold 2 hcbk_FederalFundsSoldAndOtherOvernightDeposits hcbk false debit instant Federal Funds Sold and Other Overnight Deposits. false false false false false false false false false false false terselabel false 1 false true false false 485479000 485479000 false false false 2 false false false false 0 0 false false false 3 false true false false 362449000 362449000 false false false xbrli:monetaryItemType monetary Federal Funds Sold and Other Overnight Deposits. No authoritative reference available. false 21 Investment securities held to maturity 2 hcbk_InvestmentSecuritiesHeldToMaturity hcbk false debit instant Investment Securities Held To Maturity. false false false false false false false false false false false terselabel false 1 false true false false 4939922000 4939922000 false false false 2 false false false false 0 0 false false false 3 false true false false 4187704000 4187704000 false false false xbrli:monetaryItemType monetary Investment Securities Held To Maturity. No authoritative reference available. false 22 Investment securities available for sale 2 hcbk_InvestmentSecuritiesAvailableForSale hcbk false debit instant Investment Securities Available For Sale. false false false false false false false false false false false terselabel false 1 false true false false 90797000 90797000 false false false 2 false false false false 0 0 false false false 3 false true false false 1095240000 1095240000 false false false xbrli:monetaryItemType monetary Investment Securities Available For Sale. No authoritative reference available. false 23 Federal Home Loan Bank of New York stock 2 us-gaap_FederalHomeLoanBankStock us-gaap true debit instant No definition available. false false false false false false false false false false false terselabel false 1 false true false false 878690000 878690000 false false false 2 false false false false 0 0 false false false 3 false true false false 874768000 874768000 false false false xbrli:monetaryItemType monetary Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 12 -Paragraph 26 -IssueDate 2006-05-01 false 24 Mortgage-backed securities held to maturity 2 hcbk_MortgageBackedSecuritiesHeldToMaturity hcbk false debit instant Mortgage backed Securities Held To Maturity false false false false false false false false false false false terselabel false 1 false true false false 6777579000 6777579000 false false false 2 false false false false 0 0 false false false 3 false true false false 9963554000 9963554000 false false false xbrli:monetaryItemType monetary Mortgage backed Securities Held To Maturity No authoritative reference available. false 25 Mortgage-backed securities available for sale 2 hcbk_MortgageBackedSecuritiesAvailableForSale hcbk false debit instant Mortgage-backed securities. false false false false false false false false false false false verboselabel false 1 false true false false 14961441000 14961441000 false false false 2 false false false false 0 0 false false false 3 false true false false 11116531000 11116531000 false false false xbrli:monetaryItemType monetary Mortgage-backed securities. No authoritative reference available. false 26 Loans 2 us-gaap_LoansAndLeasesReceivableNetReportedAmount us-gaap true debit instant No definition available. false false false false false false false false false false false terselabel false 1 false true false false 31626561000 31626561000 false false false 2 false false false false 0 0 false false false 3 false true false false 31721154000 31721154000 false false false xbrli:monetaryItemType monetary Reflects the aggregate carrying amount of all categories of loans and leases held in portfolio, net of unearned income and the allowance for losses on loans and leases. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 13 -Subparagraph e false 27 Estimated Fair Value of financial instruments, Assets: 2 us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 28 Cash and due from banks, Fair Value 2 hcbk_CashAndDueFromBanksFairValueDisclosure hcbk false debit instant Cash And Due From Banks Fair Value Disclosure. false false false false false false false false false false false verboselabel false 1 false true false false 147614000 147614000 false false false 2 false false false false 0 0 false false false 3 false true false false 198752000 198752000 false false false xbrli:monetaryItemType monetary Cash And Due From Banks Fair Value Disclosure. No authoritative reference available. false 29 Federal funds sold, Fair Value 2 us-gaap_FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 485479000 485479000 false false false 2 false false false false 0 0 false false false 3 false true false false 362449000 362449000 false false false xbrli:monetaryItemType monetary This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. The amount shown on an entity's books for federal funds sold and securities borrowed or purchased under agreements to resell. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 14 -Paragraph 4 -IssueDate 2006-05-01 false 30 Investment securities held to maturity, Fair Value 2 hcbk_InvestmentSecuritiesHeldToMaturityFairValueDisclosure hcbk false debit instant Investment Securities Held to Maturity Fair Value. false false false false false false false false false false false verboselabel false 1 false true false false 4967621000 4967621000 false false false 2 false false false false 0 0 false false false 3 false true false false 4071005000 4071005000 false false false xbrli:monetaryItemType monetary Investment Securities Held to Maturity Fair Value. No authoritative reference available. false 31 Investment securities available for sale, Fair Value 2 hcbk_InvestmentSecuritiesAvailableForSaleFairValueDisclosure hcbk false debit instant Investment Securities Available for Sale Fair Value. false false false false false false false false false false false terselabel false 1 false true false false 90797000 90797000 false false false 2 false false false false 0 0 false false false 3 false true false false 1095240000 1095240000 false false false xbrli:monetaryItemType monetary Investment Securities Available for Sale Fair Value. No authoritative reference available. false 32 Federal Home Loan Bank of New York stock, Fair Value 2 us-gaap_InvestmentInFederalHomeLoanBankStockFairValueDisclosure us-gaap true debit instant No definition available. false false false false false false false false false false false terselabel false 1 false true false false 878690000 878690000 false false false 2 false false false false 0 0 false false false 3 false true false false 874768000 874768000 false false false xbrli:monetaryItemType monetary This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount shown on an entity's books for investments in Federal Home Loan Bank stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 12 -Paragraph 20 -IssueDate 2006-05-01 false 33 Mortgage-backed securities held to maturity, Fair Value 2 us-gaap_MortgageBackedSecuritiesHeldToMaturityFairValueDisclosure us-gaap true debit instant No definition available. false false false false false false false false false false false terselabel false 1 false true false false 7134252000 7134252000 false false false 2 false false false false 0 0 false false false 3 false true false false 10324831000 10324831000 false false false xbrli:monetaryItemType monetary This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents securitized, pay-through debt securities collateralized by real estate mortgage loans (mortgages) as of the balance sheet date which have been categorized as held-to-maturity. The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 7 -Paragraph 15 -IssueDate 2006-05-01 false 34 Mortgage-backed securities available for sale, Fair Value 2 us-gaap_MortgageBackedSecuritiesAvailableForSaleFairValueDisclosure us-gaap true debit instant No definition available. false false false false false false false false false false false terselabel false 1 false true false false 14961441000 14961441000 false false false 2 false false false false 0 0 false false false 3 false true false false 11116531000 11116531000 false false false xbrli:monetaryItemType monetary This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents securitized, pay-through debt securities collateralized by real estate mortgage loans (mortgages) as of the balance sheet date which have been categorized as available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 7 -Paragraph 15 -IssueDate 2006-05-01 false 35 Loans, Fair Value 2 us-gaap_LoansReceivableFairValueDisclosure us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 33337678000 33337678000 false false false 2 false false false false 0 0 false false false 3 false true false false 32758247000 32758247000 false false false xbrli:monetaryItemType monetary This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents loan receivable as presented on the statement of financial position which may include mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts, or any other loans which are due the Company as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 4 false 36 Carrying Amount of financial instruments, Liabilities: 2 us-gaap_LiabilitiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false terselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 37 Deposits 2 us-gaap_Deposits us-gaap true credit instant No definition available. false false false false false false false false false false false terselabel false 1 false true false false 24914621000 24914621000 false false false 2 false false false false 0 0 false false false 3 false true false false 24578048000 24578048000 false false false xbrli:monetaryItemType monetary The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 13 -Paragraph 37, 38, 39 -IssueDate 2006-05-01 false 38 Borrowed funds 2 hcbk_BorrowedFunds hcbk false credit instant Borrowed Funds. false false false false false false false false false false false verboselabel false 1 false true false false 29825000000 29825000000 false false false 2 false false false false 0 0 false false false 3 false true false false 29975000000 29975000000 false false false xbrli:monetaryItemType monetary Borrowed Funds. 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