Debt Instrument Period Of Term.

No definition available.

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- Definition

Debt Instrument Redemption Date

+ References

No definition available.

+ Details

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- Definition

Amount of penalties incurred in the satisfaction or roll-over of Federal Home Loan Bank (FHLB) advance.

+ References

No definition available.

+ Details

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- Definition

Required Minimum Amount of Aggregate Principal Amount of Debt That Remains Outstanding Immediately After Redemption In Part

+ References

No definition available.

+ Details

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

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-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Section 563c.102

-Paragraph 18

-Chapter V

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

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-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 37

-IssueDate 2006-05-01

-Chapter 15

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, collateralized financings, and capital lease obligations.

+ References

No definition available.

+ Details

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-SubTopic 10

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

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- Definition

Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of debt outstanding by type or by instrument at that time.

+ References

No definition available.

+ Details

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- Definition

Amount of repayments and penalties incurred in the satisfaction or roll-over of Federal Home Loan Bank (FHLB) advance.

+ References

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- Definition

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).

+ References

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-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The cash outflow for the payment of loan drawn from Federal Home Loan.

+ References

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-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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-Glossary Financing Activities

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- Definition

The carrying value as of the balance sheet date of securities borrowed from broker-dealers or institutions (a) to deliver them in place of securities not available because of short-sales or late or ineffective deliveries; (b) to lend them in connection with finder or conduit transactions; and (c) to be used for other purposes permitted under federal regulations.

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-Publisher FASB

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-Paragraph 30, 31, 32, 33

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-Chapter 7

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

+ References

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Debt - Additional Information (Detail) (USD $) In Millions, unless otherwise specified			1 Months Ended	3 Months Ended	12 Months Ended		1 Months Ended			1 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Jan. 31, 2013 Federal Home Loan Bank of Boston	Mar. 31, 2013 Federal Home Loan Bank of Boston	Dec. 31, 2009 Federal Home Loan Bank of Boston Y	Jul. 31, 2010 Federal Home Loan Bank of Boston	Jan. 31, 2013 Collateralized Borrowing Program	Mar. 31, 2013 Collateralized Borrowing Program	Dec. 31, 2012 Collateralized Borrowing Program	Mar. 20, 2013 Subordinated debentures (unsecured) maturing March 30, 2053
Debt Instrument [Line Items]
Aggregate principal amount										$ 175.0
Debt instrument interest rate					5.50%					6.35%
Maturity date				Jul. 30, 2020						Mar. 30, 2053
Debt Instrument Redemption Date										Mar. 30, 2018
Required Amount of Outstanding Principal Amount of Debentures after redemption in part										25.0
Advance received					125.0
Length of debt instrument					20
Securities borrowed						46.3
Weighted average fixed interest rate				3.88%
Repayment of FHLBB community development advances			46.3				46.3
Prepayment fees on FHLBB borrowings			7.8
Total payments of FHLBB borrowings			54.1
Securities held as collateral, at fair value								145.3	200.8
Aggregate amount of borrowings								125.0	171.3
Total holdings of FHLBB stock	$ 9.3	$ 9.7