Investment Securities Text Tags (Details)	9 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2022 USD ($)
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	26		23
Proceeds from Sale of Debt Securities, Available-for-sale	$ 0	$ 0
Debt Securities, Available-for-sale	$ 53,443,000		$ 67,596,000
Percentage Available-for-sale Securities	95.70%
Debt Securities, Held-to-maturity	$ 2,406,000		5,254,000
Percentage Held-to-maturity Securities	4.30%
Trading	$ 0		0
Bank Owned Life Insurance	5,100,000
Other Investments	$ 6,200,000
Mortgage-backed securities
Schedule of Investments [Line Items]
Percentage Available-for-Sale, Continuos Unrealized Loss Position	51.20%
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	6
Debt Securities, Available-for-sale	$ 27,348,000		33,579,000
US Government Agency Securities
Schedule of Investments [Line Items]
Percentage Available-for-Sale, Continuos Unrealized Loss Position	18.40%
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	2
Debt Securities, Available-for-sale	$ 9,822,000		13,785,000
Municipal Securities
Schedule of Investments [Line Items]
Percentage Available-for-Sale, Continuos Unrealized Loss Position	24.80%
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	5
Debt Securities, Available-for-sale	$ 13,228,000		15,768,000
Corporate Bonds
Schedule of Investments [Line Items]
Percentage Available-for-Sale, Continuos Unrealized Loss Position	5.50%
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	1
Debt Securities, Available-for-sale	$ 2,945,000		4,121,000
Asset-backed Securities
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	1
Debt Securities, Available-for-sale	$ 100,000		$ 343,000

Percentage Available-for-sale Securities

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Percentage Held-to-maturity Securities

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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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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