Loans and Allowance for Loan Losses, Impaired Receivables (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Impaired loans by loans class [Abstract]
Recorded Investment	$ 25,724	$ 26,535
Unpaid Principal Balance	27,535	29,585
Related Allowance	0	0
Average Recorded Investment	26,791	27,737
Commercial Real Estate [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,780	4,129
Unpaid Principal Balance	2,928	5,499
Related Allowance	0	0
Average Recorded Investment	3,611	5,375
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
First Mortgages [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	19,615	18,868
Unpaid Principal Balance	20,911	20,069
Related Allowance	0	0
Average Recorded Investment	19,696	18,683
Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	393	422
Unpaid Principal Balance	436	466
Related Allowance	0	0
Average Recorded Investment	402	459
Home Equity Lines of Credit [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,936	3,116
Unpaid Principal Balance	3,260	3,551
Related Allowance	0	0
Average Recorded Investment	3,082	3,159
New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	23,636	24,566
Unpaid Principal Balance	25,264	27,376
Related Allowance	0	0
Average Recorded Investment	24,649	25,152
New York and Other States [Member] \| Commercial Real Estate [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,780	4,129
Unpaid Principal Balance	2,928	5,499
Related Allowance	0	0
Average Recorded Investment	3,611	4,798
New York and Other States [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] \| First Mortgages [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	18,238	17,579
Unpaid Principal Balance	19,435	18,689
Related Allowance	0	0
Average Recorded Investment	18,276	17,261
New York and Other States [Member] \| Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	338	366
Unpaid Principal Balance	381	410
Related Allowance	0	0
Average Recorded Investment	347	454
New York and Other States [Member] \| Home Equity Lines of Credit [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,280	2,492
Unpaid Principal Balance	2,520	2,778
Related Allowance	0	0
Average Recorded Investment	2,415	2,578
Florida [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,088	1,969
Unpaid Principal Balance	2,271	2,209
Related Allowance	0	0
Average Recorded Investment	2,142	2,585
Florida [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] \| 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] \| First Mortgages [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	1,377	1,289
Unpaid Principal Balance	1,476	1,380
Related Allowance	0	0
Average Recorded Investment	1,420	1,422
Florida [Member] \| Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	55	56
Unpaid Principal Balance	55	56
Related Allowance	0	0
Average Recorded Investment	55	5
Florida [Member] \| Home Equity Lines of Credit [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	656	624
Unpaid Principal Balance	740	773
Related Allowance	0	0
Average Recorded Investment	$ 667	$ 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=35738203&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=35738203&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=35738203&loc=SL6953550-111524

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