SHAREHOLDERS' EQUITY AND REGULATORY CAPITAL REQUIREMENTS - Compliance with Regulatory Capital Requirements under Banking Regulations (Details) $ in Thousands	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)
Shareholders Equity And Regulatory Capital Requirements [Abstract]
Total capital to risk weighted assets actual amount	$ 151,555	$ 145,949
Total capital to risk weighted assets actual ratio	17.35	17.01
Total capital to risk weighted assets for capital adequacy purposes amount	$ 69,879	$ 68,630
Total capital to risk weighted assets for capital adequacy purposes ratio	8.0	8.0
Total capital to risk weighted assets for capital adequacy purposes well capitalized under prompt corrective action amount	$ 87,349	$ 85,787
Total capital to risk weighted assets for capital adequacy purposes well capitalized under prompt corrective action ratio	10.0	10.0
Tier 1 to risk weighted assets actual amount	$ 140,529	$ 135,196
Tier 1 to risk weighted assets actual ratio	16.09	15.76
Tier 1 to risk weighted assets for capital adequacy purposes amount	$ 52,409	$ 51,472
Tier 1to risk weighted assets for capital adequacy purposes ratio	6.0	6.0
Tier 1 to risk weighted assets well capitalized under prompt corrective action amount	$ 69,879	$ 68,630
Tier 1 to risk weighted assets well capitalized under prompt corrective action ratio	8.0	8.0
Common equity Tier 1 capital to risk weighted assets actual amount	$ 140,529	$ 135,196
Common equity Tier 1 capital to risk weighted assets actual ratio	16.09	15.76
Common equity Tier 1 to risk weighted assets for capital adequacy purposes amount	$ 39,307	$ 38,604
Common equity Tier 1 to risk weighted assets for capital adequacy purposes ratio	4.5	4.5
Common equity Tier 1 to risk weighted assets well capitalized under prompt corrective action amount	$ 56,777	$ 55,762
Common equity Tier 1 to risk weighted assets well capitalized under prompt corrective action ratio	6.5	6.5
Tier 1 capital leverage to average tangible assets actual amount	$ 140,529	$ 135,196
Tier 1 capital leverage to average tangible assets actual ratio	9.63	11.79
Tier 1 capital leverage to average tangible assets for capital adequacy purposes amount	$ 58,344	$ 45,851
Tier 1 capital leverage to average tangible assets for capital adequacy purposes ratio	4.0	4.0
Tier 1 capital leverage to average tangible assets well capitalized under prompt corrective action amount	$ 72,930	$ 57,313
Tier 1 capital leverage to average tangible assets well capitalized under prompt corrective action ratio	5.0	5.0

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Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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