Loans and Allowance for Loan Losses, Impaired Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Impaired loans by loans class [Abstract]
Recorded Investment	$ 26,621	$ 26,535
Unpaid Principal Balance	28,234	29,585
Related Allowance	0	0
Average Recorded Investment	26,609	27,737
Commercial [Member] \| Commercial Real Estate [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3,548	4,129
Unpaid Principal Balance	3,726	5,499
Related Allowance	0	0
Average Recorded Investment	3,527	5,375
Commercial [Member] \| Other [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3	0
Unpaid Principal Balance	3	0
Related Allowance	0	0
Average Recorded Investment	0	61
Real Estate Mortgage - 1 to 4 Family [Member] \| First Mortgages [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	19,869	18,868
Unpaid Principal Balance	20,989	20,069
Related Allowance	0	0
Average Recorded Investment	19,711	18,683
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	521	422
Unpaid Principal Balance	564	466
Related Allowance	0	0
Average Recorded Investment	417	459
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Lines of Credit [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,680	3,116
Unpaid Principal Balance	2,952	3,551
Related Allowance	0	0
Average Recorded Investment	2,954	3,159
New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	24,661	24,566
Unpaid Principal Balance	26,098	27,376
Related Allowance	0	0
Average Recorded Investment	24,555	25,152
New York and Other States [Member] \| Commercial [Member] \| Commercial Real Estate [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3,548	4,129
Unpaid Principal Balance	3,726	5,499
Related Allowance	0	0
Average Recorded Investment	3,527	4,798
New York and Other States [Member] \| Commercial [Member] \| Other [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3	0
Unpaid Principal Balance	3	0
Related Allowance	0	0
Average Recorded Investment	0	61
New York and Other States [Member] \| Real Estate Mortgage - 1 to 4 Family [Member] \| First Mortgages [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	18,614	17,579
Unpaid Principal Balance	19,642	18,689
Related Allowance	0	0
Average Recorded Investment	18,372	17,261
New York and Other States [Member] \| Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	467	366
Unpaid Principal Balance	510	410
Related Allowance	0	0
Average Recorded Investment	362	454
New York and Other States [Member] \| Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Lines of Credit [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,029	2,492
Unpaid Principal Balance	2,217	2,778
Related Allowance	0	0
Average Recorded Investment	2,294	2,578
Florida [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	1,960	1,969
Unpaid Principal Balance	2,136	2,209
Related Allowance	0	0
Average Recorded Investment	2,054	2,585
Florida [Member] \| Commercial [Member] \| Commercial Real Estate [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	577
Florida [Member] \| Commercial [Member] \| Other [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Florida [Member] \| Real Estate Mortgage - 1 to 4 Family [Member] \| First Mortgages [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	1,255	1,289
Unpaid Principal Balance	1,347	1,380
Related Allowance	0	0
Average Recorded Investment	1,339	1,422
Florida [Member] \| Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	54	56
Unpaid Principal Balance	54	56
Related Allowance	0	0
Average Recorded Investment	55	5
Florida [Member] \| Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Lines of Credit [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	651	624
Unpaid Principal Balance	735	773
Related Allowance	0	0
Average Recorded Investment	$ 660	$ 581

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524

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