Note 5 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Recorded investment, with no related allowance recorded	$ 18,370		$ 18,370		$ 18,869
Unpaid principal balance, with no related allowance recorded	27,458		27,458		28,156
Recorded investment, with an allowance recorded	3,441		3,441		6,650
Unpaid principal balance, with an allowance recorded	3,441		3,441		6,650
Related allowance	309		309		1,160
Loans designated as criticized or classified	48,540		48,540		53,030
Average Recorded Investment, With no related allowance recorded	18,780	$ 47,351	18,926	$ 41,870
Interest Income Recognized, With no related allowance recorded	59	713	236	1,470
Average Recorded Investment, With an allowance recorded	3,374	3,643	4,239	3,816
Interest Income Recognized, With an allowance recorded	30	42	94	142
Multi-family Residential Portfolio Segment [Member]
Loans designated as criticized or classified	5,710		5,710		6,664
Commercial Real Estate Portfolio Segment [Member]
Loans designated as criticized or classified	10,538		10,538		4,432
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Loans designated as criticized or classified	3,004		3,004		3,233
One-To-Four Family - Residential Portfolio Segment [Member]
Loans designated as criticized or classified	6,063		6,063		7,222
Construction Portfolio Segment [Member]
Loans designated as criticized or classified	0		0		730
Small Business Administration Portfolio Segment [Member]
Loans designated as criticized or classified	140		140		620
Taxi Medallion Portfolio Segment [Member]
Loans designated as criticized or classified	3,513		3,513		4,539
Commercial Business and Other Portfolio Segment [Member]
Loans designated as criticized or classified	19,572		19,572		25,590
Mortgage Receivable [Member]
Related allowance	193		193		294
Loans designated as criticized or classified	14,177		14,177		15,922
Unpaid principal balance, total impaired loans	14,736		14,736		16,618
Average Recorded Investment, Total Impaired Loans	14,717	23,505	15,240	24,986
Interest Income Recognized, Total Impaired Loans	57	154	192	522
Mortgage Receivable [Member] \| Multi-family Residential Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	3,939		3,939		3,225
Unpaid principal balance, with no related allowance recorded	4,438		4,438		3,568
Recorded investment, with an allowance recorded	1,256		1,256		1,275
Unpaid principal balance, with an allowance recorded	1,256		1,256		1,275
Related allowance	94		94		100
Average Recorded Investment, With no related allowance recorded	3,398	4,013	3,214	4,201
Interest Income Recognized, With no related allowance recorded	9	31	27	67
Average Recorded Investment, With an allowance recorded	1,260	1,740	1,266	1,896
Interest Income Recognized, With an allowance recorded	18	19	54	78
Mortgage Receivable [Member] \| Commercial Real Estate Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	949		949		1,435
Unpaid principal balance, with no related allowance recorded	949		949		1,435
Average Recorded Investment, With no related allowance recorded	1,252	4,587	1,259	5,300
Interest Income Recognized, With no related allowance recorded	0	50	15	176
Average Recorded Investment, With an allowance recorded			0	1,206
Interest Income Recognized, With an allowance recorded			0	39
Mortgage Receivable [Member] \| One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	1,345		1,345		1,913
Unpaid principal balance, with no related allowance recorded	1,347		1,347		2,113
Recorded investment, with an allowance recorded	847		847		1,185
Unpaid principal balance, with an allowance recorded	847		847		1,185
Related allowance	51		51		143
Average Recorded Investment, With no related allowance recorded	1,889	3,452	1,919	3,759
Interest Income Recognized, With no related allowance recorded	17	28	51	108
Average Recorded Investment, With an allowance recorded	922	1,201	1,008	407
Interest Income Recognized, With an allowance recorded	8	15	28	12
Mortgage Receivable [Member] \| One-To-Four Family - Residential Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	5,454		5,454		6,490
Unpaid principal balance, with no related allowance recorded	5,512		5,512		6,643
Recorded investment, with an allowance recorded	387		387		399
Unpaid principal balance, with an allowance recorded	387		387		399
Related allowance	48		48		51
Average Recorded Investment, With no related allowance recorded	5,607	7,742	5,943	7,974
Interest Income Recognized, With no related allowance recorded	1	7	5	32
Average Recorded Investment, With an allowance recorded	389	405	393	0
Interest Income Recognized, With an allowance recorded	4	4	12	0
Mortgage Receivable [Member] \| Construction Portfolio Segment [Member]
Average Recorded Investment, With no related allowance recorded	0	365	238	243
Interest Income Recognized, With no related allowance recorded	0	0	0	10
Non-Mortgage Loans [Member]
Related allowance	116		116		866
Loans designated as criticized or classified	7,634		7,634		9,597
Unpaid principal balance, total impaired loans	16,163		16,163		18,188
Average Recorded Investment, Total Impaired Loans	7,437	27,489	7,925	20,700
Interest Income Recognized, Total Impaired Loans	32	601	138	1,090
Non-Mortgage Loans [Member] \| Small Business Administration Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	1,151		1,151		1,267
Unpaid principal balance, with no related allowance recorded	1,421		1,421		1,609
Average Recorded Investment, With no related allowance recorded	1,188	739	1,217	526
Interest Income Recognized, With no related allowance recorded	0	31	0	33
Non-Mortgage Loans [Member] \| Taxi Medallion Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	3,513		3,513		4,539
Unpaid principal balance, with no related allowance recorded	9,731		9,731		12,788
Average Recorded Investment, With no related allowance recorded	3,534	6,152	3,875	6,307
Interest Income Recognized, With no related allowance recorded	32	84	138	252
Non-Mortgage Loans [Member] \| Commercial Business and Other Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	2,019		2,019		0
Unpaid principal balance, with no related allowance recorded	4,060		4,060		0
Recorded investment, with an allowance recorded	951		951		3,791
Unpaid principal balance, with an allowance recorded	951		951		3,791
Related allowance	116		116		$ 866
Average Recorded Investment, With no related allowance recorded	1,912	20,301	1,261	13,560
Interest Income Recognized, With no related allowance recorded	0	482	0	792
Average Recorded Investment, With an allowance recorded	803	297	1,572	307
Interest Income Recognized, With an allowance recorded	$ 0	$ 4	$ 0	$ 13

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
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