Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Assets [Abstract]
Allowance for loan losses	$ 3,296	$ 3,215
Stockholders' Equity:
Treasury stock, shares (in shares)	2,617,826	2,617,826
Cumulative Redeemable Perpetual Preferred stock, Series A [Member]
Stockholders' Equity:
Preferred stock, shares authorized (in shares)	3,000	0
Preferred stock, shares issued (in shares)	3,000	0
Preferred stock, shares outstanding (in shares)	3,000	0
Preferred stock, liquidation value (in dollars per share)	$ 1,000	$ 1,000
Class A Voting Common Stock [Member]
Stockholders' Equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	75,000,000	50,000,000
Common stock, shares issued (in shares)	46,248,710	21,899,584
Common stock, shares outstanding (in shares)	43,630,884	19,281,758
Class B Non-Voting Common Stock [Member]
Stockholders' Equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	15,000,000	0
Common stock, shares issued (in shares)	11,404,621	0
Common stock, shares outstanding (in shares)	11,404,621	0
Class C Non-Voting Common Stock [Member]
Stockholders' Equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	25,000,000	25,000,000
Common stock, shares issued (in shares)	16,689,775	8,756,396
Common stock, shares outstanding (in shares)	16,689,775	8,756,396