Note 9 - Allowance for Loan Losses and Credit Quality Information - Allowance for Loan Losses (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Dec. 31, 2015
One to Four Family Porfolio Segment [Member]
Balance, beginning	$ 1,270,000	$ 1,011,000	$ 990,000	$ 1,096,000
Provision for loan losses	31,000	117,000	311,000	30,000
Charge-offs	(66,000)	(19,000)	(66,000)	(19,000)
Recoveries	0	1,000	0	3,000
Balance, ending	1,235,000	1,110,000	1,235,000	1,110,000
Specific reserves					$ 242,000	$ 223,000
General reserves					993,000	767,000
Loans and Leases Receivable, Allowance	1,270,000	1,011,000	1,235,000	1,110,000	1,235,000	990,000
Individually reviewed for impairment					1,351,000	2,203,000
Collectively reviewed for impairment					99,285,000	88,742,000
Ending balance					100,636,000	90,945,000
Commercial Real Estate Portfolio Segment [Member]
Balance, beginning	5,827,000	5,278,000	6,078,000	5,024,000
Provision for loan losses	(288,000)	(462,000)	(1,148,000)	(415,000)
Charge-offs	(67,000)	0	(67,000)	0
Recoveries	48,000	435,000	657,000	642,000
Balance, ending	5,520,000	5,251,000	5,520,000	5,251,000
Specific reserves					414,000	296,000
General reserves					5,106,000	5,782,000
Loans and Leases Receivable, Allowance	5,827,000	5,278,000	5,520,000	5,251,000	5,520,000	6,078,000
Individually reviewed for impairment					3,350,000	2,204,000
Collectively reviewed for impairment					296,019,000	245,149,000
Ending balance					299,369,000	247,353,000
Consumer Portfolio Segment [Member]
Balance, beginning	1,531,000	1,162,000	1,200,000	1,009,000
Provision for loan losses	116,000	25,000	432,000	191,000
Charge-offs	(14,000)	(39,000)	(29,000)	(66,000)
Recoveries	4,000	7,000	34,000	21,000
Balance, ending	1,637,000	1,155,000	1,637,000	1,155,000
Specific reserves					416,000	370,000
General reserves					1,221,000	830,000
Loans and Leases Receivable, Allowance	1,531,000	1,162,000	1,637,000	1,155,000	1,637,000	1,200,000
Individually reviewed for impairment					916,000	977,000
Collectively reviewed for impairment					75,151,000	63,438,000
Ending balance					76,067,000	64,415,000
Commercial Portfolio Segment [Member]
Balance, beginning	1,697,000	951,000	1,441,000	1,203,000
Provision for loan losses	221,000	264,000	134,000	(45,000)
Charge-offs	(56,000)	(1,000)	(100,000)	(6,000)
Recoveries	52,000	56,000	439,000	118,000
Balance, ending	1,914,000	1,270,000	1,914,000	1,270,000
Specific reserves					184,000	120,000
General reserves					1,730,000	1,321,000
Loans and Leases Receivable, Allowance	1,697,000	951,000	1,914,000	1,270,000	1,914,000	1,441,000
Individually reviewed for impairment					730,000	415,000
Collectively reviewed for impairment					73,785,000	69,691,000
Ending balance					74,515,000	70,106,000
Balance, beginning	10,325,000	8,402,000	9,709,000	8,332,000
Provision for loan losses	80,000	(56,000)	(271,000)	(239,000)
Charge-offs	(203,000)	(59,000)	(262,000)	(91,000)
Recoveries	104,000	499,000	1,130,000	784,000
Balance, ending	10,306,000	8,786,000	10,306,000	8,786,000
Specific reserves					1,256,000	1,009,000
General reserves					9,050,000	8,700,000
Loans and Leases Receivable, Allowance	$ 10,306,000	$ 8,402,000	$ 10,306,000	$ 8,786,000	10,306,000	9,709,000
Individually reviewed for impairment					6,347,000	5,799,000
Collectively reviewed for impairment					544,240,000	467,020,000
Ending balance					$ 550,587,000	$ 472,819,000