Loans and Allowance for Loan Losses, Impaired Receivables (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Impaired loans by loans class [Abstract]
Recorded Investment	$ 27,120	$ 26,535
Unpaid Principal Balance	28,634	29,585
Related Allowance	0	0
Average Recorded Investment	28,780	27,737
Commercial [Member] \| Commercial Real Estate [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3,984	4,129
Unpaid Principal Balance	4,162	5,499
Related Allowance	0	0
Average Recorded Investment	3,612	5,375
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	61
Real Estate Mortgage - 1 to 4 Family [Member] \| First Mortgages [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	19,902	18,868
Unpaid Principal Balance	20,933	20,069
Related Allowance	0	0
Average Recorded Investment	21,105	18,683
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	471	422
Unpaid Principal Balance	498	466
Related Allowance	0	0
Average Recorded Investment	492	459
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Lines of Credit [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,763	3,116
Unpaid Principal Balance	3,041	3,551
Related Allowance	0	0
Average Recorded Investment	3,571	3,159
New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	24,652	24,566
Unpaid Principal Balance	25,990	27,376
Related Allowance	0	0
Average Recorded Investment	26,654	25,152
New York and Other States [Member] \| Commercial [Member] \| Commercial Real Estate [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3,984	4,129
Unpaid Principal Balance	4,162	5,499
Related Allowance	0	0
Average Recorded Investment	3,612	4,798
New York and Other States [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	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	18,130	17,579
Unpaid Principal Balance	19,069	18,689
Related Allowance	0	0
Average Recorded Investment	19,708	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	418	366
Unpaid Principal Balance	445	410
Related Allowance	0	0
Average Recorded Investment	438	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	2,120	2,492
Unpaid Principal Balance	2,314	2,778
Related Allowance	0	0
Average Recorded Investment	2,896	2,578
Florida [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,468	1,969
Unpaid Principal Balance	2,644	2,209
Related Allowance	0	0
Average Recorded Investment	2,126	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	1,772	1,289
Unpaid Principal Balance	1,864	1,380
Related Allowance	0	0
Average Recorded Investment	1,397	1,422
Florida [Member] \| Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	53	56
Unpaid Principal Balance	53	56
Related Allowance	0	0
Average Recorded Investment	54	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	643	624
Unpaid Principal Balance	727	773
Related Allowance	0	0
Average Recorded Investment	$ 675	$ 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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