Loans and Allowance for Loan Losses, Impaired Receivables (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Impaired loans by loans class [Abstract]
Recorded Investment	$ 25,790	$ 24,025
Unpaid Principal Balance	27,890	26,201
Related Allowance	0	0
Average Recorded Investment	25,100	22,408
New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	22,665	21,361
Unpaid Principal Balance	24,601	23,374
Related Allowance	0	0
Average Recorded Investment	22,251	19,936
Florida [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3,125	2,664
Unpaid Principal Balance	3,289	2,827
Related Allowance	0	0
Average Recorded Investment	2,849	2,472
Commercial [Member] \| Commercial Real Estate [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3,908	2,418
Unpaid Principal Balance	4,955	3,470
Related Allowance	0	0
Average Recorded Investment	2,883	2,214
Commercial [Member] \| Commercial Real Estate [Member] \| New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	3,908	2,418
Unpaid Principal Balance	4,955	3,470
Related Allowance	0	0
Average Recorded Investment	2,883	2,214
Commercial [Member] \| Commercial Real Estate [Member] \| Florida [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
Commercial [Member] \| Other [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	100	0
Unpaid Principal Balance	100	0
Related Allowance	0	0
Average Recorded Investment	100	0
Commercial [Member] \| Other [Member] \| New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	100	0
Unpaid Principal Balance	100	0
Related Allowance	0	0
Average Recorded Investment	100	0
Commercial [Member] \| Other [Member] \| Florida [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
Real Estate Mortgage - 1 to 4 Family [Member] \| First Mortgages [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	18,796	18,684
Unpaid Principal Balance	19,557	19,539
Related Allowance	0	0
Average Recorded Investment	19,116	17,465
Real Estate Mortgage - 1 to 4 Family [Member] \| First Mortgages [Member] \| New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	16,350	16,675
Unpaid Principal Balance	17,019	17,439
Related Allowance	0	0
Average Recorded Investment	16,939	15,665
Real Estate Mortgage - 1 to 4 Family [Member] \| First Mortgages [Member] \| Florida [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,446	2,009
Unpaid Principal Balance	2,538	2,100
Related Allowance	0	0
Average Recorded Investment	2,177	1,800
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Loans [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	357	363
Unpaid Principal Balance	393	399
Related Allowance	0	0
Average Recorded Investment	363	332
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Loans [Member] \| New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	265	269
Unpaid Principal Balance	301	305
Related Allowance	0	0
Average Recorded Investment	270	251
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Loans [Member] \| Florida [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	92	94
Unpaid Principal Balance	92	94
Related Allowance	0	0
Average Recorded Investment	93	81
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Lines of Credit [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,629	2,560
Unpaid Principal Balance	2,885	2,793
Related Allowance	0	0
Average Recorded Investment	2,639	2,397
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Lines of Credit [Member] \| New York and Other States [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	2,042	1,999
Unpaid Principal Balance	2,226	2,160
Related Allowance	0	0
Average Recorded Investment	2,060	1,806
Real Estate Mortgage - 1 to 4 Family [Member] \| Home Equity Lines of Credit [Member] \| Florida [Member]
Impaired loans by loans class [Abstract]
Recorded Investment	587	561
Unpaid Principal Balance	659	633
Related Allowance	0	0
Average Recorded Investment	$ 579	$ 591

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=66008989&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=66008989&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=66008989&loc=SL6953550-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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