Borrowings (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Available-for-sale securities pledged as collateral	$ 4.8	$ 5.2
Federal Home Loan Bank of New York [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Loans pledged as collateral	207.5
Maximum amount of funding available	167.7
Line of credit facility [Abstract]
Amount outstanding	41.7
Atlantic Central Bankers' Bank [Member]
Line of credit facility [Abstract]
Maximum borrowing capacity	6.0
Amount outstanding	0.0	0.0
Other Financial Institution [Member]
Line of credit facility [Abstract]
Maximum borrowing capacity	5.0
Amount outstanding	$ 0.0	$ 0.0
Fixed Rate Term Borrowing [Member] \| Federal Home Loan Bank of New York [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Weighted average interest rate (in hundredths)	1.48%
Weighted average maturity	40 months
Maturity Overnight [Member] \| Federal Home Loan Bank of New York [Member]
Line of credit facility [Abstract]
Amount outstanding	$ 22.9
Maturity Overnight [Member] \| Federal Reserve Bank [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Available-for-sale securities pledged as collateral	4.8
Standby Letters of Credit [Member] \| Federal Home Loan Bank of New York [Member]
Line of credit facility [Abstract]
Amount outstanding	$ 0.0

The fair value of available-for-sale securities that serve as collateral for borrowings.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ 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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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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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Maturity period on fixed rate advances made and reported by Federal Home Loan Bank (FHLBank), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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