Consolidated Statements of Changes in Stockholders' Equity and Retained Earnings (Unaudited) - USD ($)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Unearned Compensation ESOP [Member]
Beginning Balance at Jun. 30, 2020	$ 47,246,000			$ 47,236,000	$ 10,000
Comprehensive income (loss)	593,000			595,000	(2,000)
Ending Balance at Dec. 31, 2020	47,839,000			47,831,000	8,000
Beginning Balance at Jun. 30, 2020	47,246,000			47,236,000	10,000
Comprehensive income (loss)	981,000
Ending Balance at Mar. 31, 2021	48,227,000			48,232,000	(5,000)
Beginning Balance at Dec. 31, 2020	47,839,000			47,831,000	8,000
Comprehensive income (loss)	388,000			401,000	(13,000)
Ending Balance at Mar. 31, 2021	48,227,000			48,232,000	(5,000)
Beginning Balance (in shares) at Jun. 30, 2021		0
Beginning Balance at Jun. 30, 2021	48,645,000	$ 0	$ 0	48,628,000	17,000	$ 0
Comprehensive income (loss)	462,000	$ 0	0	472,000	(10,000)	0
Ending Balance (in shares) at Sep. 30, 2021		0
Ending Balance at Sep. 30, 2021	49,107,000	$ 0	0	49,100,000	7,000	0
Beginning Balance (in shares) at Jun. 30, 2021		0
Beginning Balance at Jun. 30, 2021	48,645,000	$ 0	0	48,628,000	17,000	0
Comprehensive income (loss)	(135,000)
Ending Balance (in shares) at Mar. 31, 2022		6,521,642
Ending Balance at Mar. 31, 2022	73,659,000	$ 65,000	27,720,000	48,406,000	4,000	(2,536,000)
Beginning Balance (in shares) at Sep. 30, 2021		0
Beginning Balance at Sep. 30, 2021	49,107,000	$ 0	0	49,100,000	7,000	0
Comprehensive income (loss)	233,000	$ 0	0	234,000	(1,000)	0
Ending Balance (in shares) at Dec. 31, 2021		0
Ending Balance at Dec. 31, 2021	49,340,000	$ 0	0	49,334,000	6,000	0
Comprehensive income (loss)	(830,000)	0	0	(828,000)	(2,000)	0
Transfer of cash from CFSB to 15 Beach MHC	(100,000)	$ 0	0	(100,000)	0	0
Issuance of shares to the mutual holding company (in shares)		3,586,903
Issuance of shares to the mutual holding company	36,000	$ 36,000	0	0	0	0
Issuance of shares in the intial public offering, net of expenses	26,445,000	$ 28,000	26,417,000	0	0	0
Issuance of shares in the intial public offering, net of expenses (in shares)		2,804,306
Issuance and contribution of shares to the Colonial Federal Savings Bank Charitable Foundation	1,304,000	$ 1,000	1,303,000	0	0	0
Issuance and contribution of shares to the Colonial Federal Savings Bank Charitable Foundation (in shares)		130,433
Purchase of shares by the ESOP	2,556,000	$ 0	0	0	0	(2,556,000)
ESOP shares committed to be released	20,000					20,000
Ending Balance (in shares) at Mar. 31, 2022		6,521,642
Ending Balance at Mar. 31, 2022	$ 73,659,000	$ 65,000	$ 27,720,000	$ 48,406,000	$ 4,000	$ (2,536,000)