Federal Home Loan Bank Advances - Additional Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Mar. 31, 2013
Securities Pledged As Collateral [Line Items]
Long-term Federal Home Loan Bank Advances	$ 46,508	$ 46,557
Maximum borrowing capacity of the Bank		69,706
Cash management line of credit		40,000
Prepayments For Federal Home Loan Bank Advances	27,500
Federal Home Loan Bank advances, average interest rate	2.47%
Federal Home Loan Bank advances contractual average interest rate	0.88%
Deferred FHLB prepayment penalty	1,017
Cash Management Line Of Credit Outstanding	0	0
Multi-family mortgage loans [Member]
Securities Pledged As Collateral [Line Items]
Investment securities		79,147
Residential real estate mortgage loans [Member]
Securities Pledged As Collateral [Line Items]
Investment securities		$ 24,168
Minimum [Member]
Securities Pledged As Collateral [Line Items]
Federal Home Loan Bank advances remaining maturity	12 months
Federal Home Loan Bank advances, fixed rate, remaining maturity	49 months
Maximum [Member]
Securities Pledged As Collateral [Line Items]
Federal Home Loan Bank advances remaining maturity	31 months
Federal Home Loan Bank advances, fixed rate, remaining maturity	67 months

Cash management line of credit.

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Cash management line of credit outstanding.

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- Definition

Federal Home Loan Bank, Advances, Fixed Rate, Disclosures, Remaining Maturity

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Federal Home Loan Bank, Advances, Prepaid, Disclosures, Remaining Maturity

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Federal Home Loan Bank, Advances, Prepayment Penalty

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Prepayments For Federal Home Loan Bank Advances

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Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

+ References

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 14

-Subparagraph e

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- Definition

The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date.

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States the weighted average interest rate applicable to the advances from the Federal Home Loan Bank outstanding as of the Balance Sheet date.

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-Publisher SEC

-Name Industry Guide

-Number 3

-Section VII

-Subsection 1

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

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-Publisher OTS

-Name Federal Regulation (FR)

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-Paragraph 15, 18

-Chapter V

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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