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Subordinated Debentures and Rescinded Stock Obligation - Additional Information (Detail) (USD $)
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3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | ||
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Sep. 30, 2014
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Sep. 30, 2014
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Aug. 31, 2014
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Sep. 30, 2014
Central Bancorp, Inc [Member]
Subordinated Debentures [Member]
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Sep. 30, 2014
Central Bancorp, Inc [Member]
Subordinated Debentures [Member]
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Dec. 31, 2005
Central Bancorp, Inc [Member]
Subordinated Debentures [Member]
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| Debt Instrument [Line Items] | ||||||
| Subordinated debentures, notional amount | $ 26,800,000 | $ 26,800,000 | $ 26,000,000 | |||
| Subordinated debentures | 18,509,000 | 18,509,000 | 18,500,000 | 18,500,000 | ||
| Debt instrument discount | 8,300,000 | 8,300,000 | 8,300,000 | |||
| Fixed interest rate | 6.26% | |||||
| Variable interest rate basis | 3 month LIBOR plus 140 basis | |||||
| Maturity date of subordinated debentures | Dec. 31, 2035 | |||||
| Frequency of interest payment | Quarterly | |||||
| Amortization of subordinated debentures | 35,000 | 36,000 | 35,000 | |||
| Rescinded stock obligation | 15,720,000 | 15,720,000 | ||||
| Accrued interest payable | 5,100,000 | 5,100,000 | 4,900,000 | |||
| Interest on rescinded stock obligation | $ 87,000 | $ 87,000 | ||||
| Weighted average interest rate | 6.79% | 6.79% |
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- Definition
Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. No definition available.
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- Definition
Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Description of the frequency of periodic payments (monthly, quarterly, annual). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Weighted average interest rate of debt outstanding. No definition available.
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- Definition
Interest expense incurred during the reporting period on capital securities issued by the reporting entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount that would be paid, determined under the conditions specified in the contract, if the holder of the share has the right to redeem the shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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