Consolidated Statements of Financial Condition (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Securities held to maturity, fair value	$ 35,696	$ 38,569
Loans receivable, allowance for loan losses	$ 5,722	$ 5,655
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	49,000,000	49,000,000
Common stock, share issued (in shares)	5,184,914	5,389,054
Common stock, share outstanding (in shares)	5,184,914	5,389,054
Unallocated common stock held by ESOP, shares (in shares)	168,538	179,464