Note 5 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Recorded investment, with no related allowance recorded	$ 19,274		$ 18,869
Unpaid principal balance, with no related allowance recorded	28,470		28,156
Recorded investment, with an allowance recorded	3,559		6,650
Unpaid principal balance, with an allowance recorded	3,559		6,650
Related allowance	380		1,160
Loans designated as criticized or classified	47,194		53,030
Average Recorded Investment, With no related allowance recorded	19,072	$ 31,941
Interest Income Recognized, With no related allowance recorded	86	235
Average Recorded Investment, With an allowance recorded	5,105	5,180
Interest Income Recognized, With an allowance recorded	32	47
Mortgage Receivable [Member]
Related allowance	202		294
Loans designated as criticized or classified	15,601		15,922
Unpaid principal balance, total impaired loans	16,238		16,618
Average Recorded Investment, Total Impaired Loans	15,763	29,743
Interest Income Recognized, Total Impaired Loans	60	192
Non-Mortgage Loans [Member]
Related allowance	178		866
Loans designated as criticized or classified	7,232		9,597
Unpaid principal balance, total impaired loans	15,791		18,188
Average Recorded Investment, Total Impaired Loans	8,414	7,378
Interest Income Recognized, Total Impaired Loans	58	90
Multi-family Residential Portfolio Segment [Member]
Loans designated as criticized or classified	5,260		6,664
Multi-family Residential Portfolio Segment [Member] \| Mortgage Receivable [Member]
Recorded investment, with no related allowance recorded	2,835		3,225
Unpaid principal balance, with no related allowance recorded	3,179		3,568
Recorded investment, with an allowance recorded	1,269		1,275
Unpaid principal balance, with an allowance recorded	1,269		1,275
Related allowance	98		100
Average Recorded Investment, With no related allowance recorded	3,031	4,834
Interest Income Recognized, With no related allowance recorded	9	20
Average Recorded Investment, With an allowance recorded	1,272	2,214
Interest Income Recognized, With an allowance recorded	18	29
Commercial Real Estate Portfolio Segment [Member]
Loans designated as criticized or classified	4,009		4,432
Commercial Real Estate Portfolio Segment [Member] \| Mortgage Receivable [Member]
Recorded investment, with no related allowance recorded	1,097		1,435
Unpaid principal balance, with no related allowance recorded	1,097		1,435
Average Recorded Investment, With no related allowance recorded	1,266	6,915
Interest Income Recognized, With no related allowance recorded		74
Average Recorded Investment, With an allowance recorded		993
Interest Income Recognized, With an allowance recorded
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Loans designated as criticized or classified	3,278		3,233
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member] \| Mortgage Receivable [Member]
Recorded investment, with no related allowance recorded	1,983		1,913
Unpaid principal balance, with no related allowance recorded	2,123		2,113
Recorded investment, with an allowance recorded	1,004		1,185
Unpaid principal balance, with an allowance recorded	1,004		1,185
Related allowance	54		143
Average Recorded Investment, With no related allowance recorded	1,948	4,297
Interest Income Recognized, With no related allowance recorded	17	41
Average Recorded Investment, With an allowance recorded	1,095	1,222
Interest Income Recognized, With an allowance recorded	10	9
One-To-Four Family - Residential Portfolio Segment [Member]
Loans designated as criticized or classified	6,453		7,222
One-To-Four Family - Residential Portfolio Segment [Member] \| Mortgage Receivable [Member]
Recorded investment, with no related allowance recorded	6,068		6,490
Unpaid principal balance, with no related allowance recorded	6,221		6,643
Recorded investment, with an allowance recorded	395		399
Unpaid principal balance, with an allowance recorded	395		399
Related allowance	50		51
Average Recorded Investment, With no related allowance recorded	6,279	8,855
Interest Income Recognized, With no related allowance recorded	2	15
Average Recorded Investment, With an allowance recorded	397	413
Interest Income Recognized, With an allowance recorded	4	4
Construction Portfolio Segment [Member]
Loans designated as criticized or classified	950		730
Construction Portfolio Segment [Member] \| Mortgage Receivable [Member]
Recorded investment, with no related allowance recorded	950
Unpaid principal balance, with no related allowance recorded	950
Average Recorded Investment, With no related allowance recorded	475
Interest Income Recognized, With no related allowance recorded
Small Business Administration Portfolio Segment [Member]
Loans designated as criticized or classified	594		620
Small Business Administration Portfolio Segment [Member] \| Non-Mortgage Loans [Member]
Recorded investment, with no related allowance recorded	1,227		1,267
Unpaid principal balance, with no related allowance recorded	1,499		1,609
Average Recorded Investment, With no related allowance recorded	1,247	118
Interest Income Recognized, With no related allowance recorded		1
Taxi Medallion Portfolio Segment [Member]
Loans designated as criticized or classified	3,891		4,539
Taxi Medallion Portfolio Segment [Member] \| Non-Mortgage Loans [Member]
Recorded investment, with no related allowance recorded	3,891		4,539
Unpaid principal balance, with no related allowance recorded	11,049		12,788
Average Recorded Investment, With no related allowance recorded	4,215	6,726
Interest Income Recognized, With no related allowance recorded	58	82
Average Recorded Investment, With an allowance recorded
Interest Income Recognized, With an allowance recorded
Commercial Business and Other Portfolio Segment [Member]
Loans designated as criticized or classified	22,759		25,590
Commercial Business and Other Portfolio Segment [Member] \| Non-Mortgage Loans [Member]
Recorded investment, with no related allowance recorded	1,223
Unpaid principal balance, with no related allowance recorded	2,352
Recorded investment, with an allowance recorded	891		3,791
Unpaid principal balance, with an allowance recorded	891		3,791
Related allowance	178		$ 866
Average Recorded Investment, With no related allowance recorded	611	196
Interest Income Recognized, With no related allowance recorded		2
Average Recorded Investment, With an allowance recorded	2,341	338
Interest Income Recognized, With an allowance recorded		$ 5

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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