Stock Plans (Detail Textuals) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Aug. 31, 2019	May 31, 2019
Equity Class Of Treasury Stock [Line Items]
Number of shares repurchased	77,000	25,000	137,000	30,000
Aggregate cost of shares repurchased	$ 887,000	$ 201,000	$ 1,552,000	$ 229,000
New Stock Repurchase Program | Common Stock
Equity Class Of Treasury Stock [Line Items]
Stock repurchase program, authorized amount					$ 1,000,000.0	$ 8,000,000.0
Number of shares repurchased	76,563
Aggregate cost of shares repurchased	$ 887,000
Shares repurchased, average cost per share	$ 11.25