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Investment Securities Text Tag (Details)	12 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)
Investments, Debt and Equity Securities [Abstract]
Available-for-sale	$ 67,596,000	$ 86,507,000
Percentage Available-for-sale Securities	92.80%
Debt Securities, Held-to-maturity	$ 5,254,000	7,807,000
Percentage Held-to-maturity Securities	7.20%
Debt Securities, Trading, and Equity Securities, FV-NI	$ 0
Equity securities	1,100,000
Proceeds from sales of investments: Available-for-sale	0	$ 37,802,000
Pledged Financial Instruments, Not Separately Reported, Securities for Federal Home Loan Bank	$ 5,900,000
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	23	15
Mortgage-Backed Securities
Investments, Debt and Equity Securities [Abstract]
Available-for-sale	$ 33,579,000	$ 43,421,000
Debt Securities, Held-to-maturity	$ 5,254,000
Debt Securities, Available-for-sale [Line Items]
Percentage Available-for-Sale, Continuous Unrealized Loss Position	49.40%
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	4
US Government Agency Securities
Investments, Debt and Equity Securities [Abstract]
Available-for-sale	$ 13,785,000	18,631,000
Debt Securities, Available-for-sale [Line Items]
Percentage Available-for-Sale, Continuous Unrealized Loss Position	20.50%
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	3
Corporate Bonds
Investments, Debt and Equity Securities [Abstract]
Available-for-sale	$ 4,121,000	4,481,000
Debt Securities, Available-for-sale [Line Items]
Percentage Available-for-Sale, Continuous Unrealized Loss Position	6.10%
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	1
Municipal Bonds
Investments, Debt and Equity Securities [Abstract]
Available-for-sale	$ 15,768,000	$ 16,610,000
Debt Securities, Available-for-sale [Line Items]
Percentage Available-for-Sale, Continuous Unrealized Loss Position	23.50%
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	1

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for FHLB debt obligations, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

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