Note 3 - Loans Receivable - Credit Quality Indicators (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Loans receivable	$ 1,664,817		$ 1,664,215
Originated current year	36,781		457,414
Originated one years before	459,739		461,197
Originated two years before	446,093		255,554
Originated three years before	250,267		189,398
Originated four years before	186,942		86,529
Originated five years before	263,507		189,667
Revolving	21,488		24,456
Gross charge-offs, current year	3
Gross charge-offs, one year before	0
Gross charge-offs, two years before	0
Gross charge-offs, three years before	0
Gross charge-offs, four years before	0
Gross charge-offs, five years before	0
Gross charge-offs, revolving	8
Gross charge-offs, total	11	$ 24
Residential Portfolio Segment [Member] | One to Four Family [Member]
Loans receivable	551,005		551,190
Originated current year	18,663		202,798
Originated one years before	195,309		167,621
Originated two years before	161,912		46,378
Originated three years before	44,322		33,295
Originated four years before	33,048		19,966
Originated five years before	96,636		80,205
Revolving	1,115		927
Gross charge-offs, total	3	3
Residential Portfolio Segment [Member] | Multifamily [Member]
Loans receivable	702,487		707,566
Originated current year	8,271		122,480
Originated one years before	123,507		214,080
Originated two years before	209,783		135,823
Originated three years before	134,109		117,669
Originated four years before	116,823		44,878
Originated five years before	109,139		71,818
Revolving	855		818
Gross charge-offs, total	(0)	(0)
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Loans receivable	13,664		13,228
Originated current year	1,059		1,084
Originated one years before	1,075		273
Originated two years before	248		178
Originated three years before	174		98
Originated four years before	96		87
Originated five years before	404		342
Revolving	10,608		11,166
Gross charge-offs, total	(0)	(0)
Construction and Land Portfolio Segment [Member]
Loans receivable	64,431		53,371
Originated current year	1,851		38,079
Originated one years before	47,561		1,348
Originated two years before	1,782		9,349
Originated three years before	9,298		2,146
Originated four years before	1,547		2,255
Originated five years before	2,392		194
Revolving	0		0
Gross charge-offs, total	(0)	(0)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	297,341		300,892
Originated current year	6,807		75,954
Originated one years before	75,053		76,196
Originated two years before	70,798		62,922
Originated three years before	61,543		33,522
Originated four years before	32,892		19,250
Originated five years before	49,447		31,673
Revolving	801		1,375
Gross charge-offs, total	(0)	(0)
Commercial Portfolio Segment [Member]
Loans receivable	35,067		37,120
Originated current year	130		17,019
Originated one years before	17,234		1,679
Originated two years before	1,570		904
Originated three years before	821		2,668
Originated four years before	2,536		93
Originated five years before	5,489		5,435
Revolving	7,287		9,322
Gross charge-offs, total	(0)	(0)
Consumer Portfolio Segment [Member]
Loans receivable	822		848
Originated current year	0		0
Originated one years before	0		0
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	822		848
Gross charge-offs, total	8	$ 21
Substandard [Member]
Loans receivable	11,411		11,621
Substandard [Member] | Residential Portfolio Segment [Member] | One to Four Family [Member]
Loans receivable	4,544		4,503
Originated current year	0		1,450
Originated one years before	1,422		353
Originated two years before	953		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	2,169		2,700
Revolving	0		0
Substandard [Member] | Residential Portfolio Segment [Member] | Multifamily [Member]
Loans receivable	0		0
Originated current year	0		0
Originated one years before	0		0
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	0		0
Substandard [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Loans receivable	199		90
Originated current year	0		0
Originated one years before	0		18
Originated two years before	16		17
Originated three years before	16		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	167		55
Substandard [Member] | Construction and Land Portfolio Segment [Member]
Loans receivable	0		0
Originated current year	0		0
Originated one years before	0		0
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	0		0
Substandard [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans receivable	5,383		5,492
Originated current year	0		5,277
Originated one years before	5,254		129
Originated two years before	129		0
Originated three years before	0		86
Originated four years before	0		0
Originated five years before	0		0
Revolving	0		0
Substandard [Member] | Commercial Portfolio Segment [Member]
Loans receivable	1,285		1,536
Originated current year	0		0
Originated one years before	0		48
Originated two years before	44		0
Originated three years before	0		0
Originated four years before	0		13
Originated five years before	6		0
Revolving	1,235		1,475
Substandard [Member] | Consumer Portfolio Segment [Member]
Loans receivable	0		0
Originated current year	0		0
Originated one years before	0		0
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	0		0
Pass [Member]
Loans receivable	1,643,129		1,644,626
Pass [Member] | Residential Portfolio Segment [Member] | One to Four Family [Member]
Loans receivable	537,714		539,102
Originated current year	12,449		196,255
Originated one years before	193,887		166,555
Originated two years before	160,494		46,378
Originated three years before	44,322		33,295
Originated four years before	33,048		19,966
Originated five years before	92,399		75,726
Revolving	1,115		927
Pass [Member] | Residential Portfolio Segment [Member] | Multifamily [Member]
Loans receivable	702,302		707,183
Originated current year	8,271		122,289
Originated one years before	123,507		214,074
Originated two years before	209,783		135,823
Originated three years before	134,109		117,669
Originated four years before	116,823		44,878
Originated five years before	108,954		71,632
Revolving	855		818
Pass [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Loans receivable	12,757		13,138
Originated current year	351		1,084
Originated one years before	1,075		255
Originated two years before	232		161
Originated three years before	158		98
Originated four years before	96		87
Originated five years before	404		342
Revolving	10,441		11,111
Pass [Member] | Construction and Land Portfolio Segment [Member]
Loans receivable	64,286		53,371
Originated current year	1,851		38,079
Originated one years before	47,561		1,348
Originated two years before	1,637		9,349
Originated three years before	9,298		2,146
Originated four years before	1,547		2,255
Originated five years before	2,392		194
Revolving	0		0
Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans receivable	291,541		295,400
Originated current year	6,807		70,677
Originated one years before	69,799		76,067
Originated two years before	70,252		62,922
Originated three years before	61,543		33,436
Originated four years before	32,892		19,250
Originated five years before	49,447		31,673
Revolving	801		1,375
Pass [Member] | Commercial Portfolio Segment [Member]
Loans receivable	33,707		35,584
Originated current year	130		17,019
Originated one years before	17,234		1,631
Originated two years before	1,526		904
Originated three years before	821		2,668
Originated four years before	2,536		80
Originated five years before	5,483		5,435
Revolving	5,977		7,847
Pass [Member] | Consumer Portfolio Segment [Member]
Loans receivable	822		848
Originated current year	0		0
Originated one years before	0		0
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	822		848
Watch [Member]
Loans receivable	10,277		7,968
Watch [Member] | Residential Portfolio Segment [Member] | One to Four Family [Member]
Loans receivable	8,747		7,585
Originated current year	6,214		5,093
Originated one years before	0		713
Originated two years before	465		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	2,068		1,779
Revolving	0		0
Watch [Member] | Residential Portfolio Segment [Member] | Multifamily [Member]
Loans receivable	185		383
Originated current year	0		191
Originated one years before	0		6
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	185		186
Revolving	0		0
Watch [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Loans receivable	708		0
Originated current year	708		0
Originated one years before	0		0
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	0		0
Watch [Member] | Construction and Land Portfolio Segment [Member]
Loans receivable	145		0
Originated current year	0		0
Originated one years before	0		0
Originated two years before	145		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	0		0
Watch [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans receivable	417		0
Originated current year	0		0
Originated one years before	0		0
Originated two years before	417		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	0		0
Watch [Member] | Commercial Portfolio Segment [Member]
Loans receivable	75		0
Originated current year	0		0
Originated one years before	0		0
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	75		0
Watch [Member] | Consumer Portfolio Segment [Member]
Loans receivable	0		0
Originated current year	0		0
Originated one years before	0		0
Originated two years before	0		0
Originated three years before	0		0
Originated four years before	0		0
Originated five years before	0		0
Revolving	$ 0		$ 0