Share-Based Payments - Summary of option activity under the equity plans (Details) - Stock options - $ / shares	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Shares
Exercised	0	(2,000)
Forfeited	(7,000)	(8,000)
Equity Plans
Shares
Outstanding at March 31, 2020	62,000
Granted	0
Exercised	0
Forfeited	(7,000)
Outstanding at March 31, 2021	55,000	62,000
Exercisable at March 31, 2021	55,000
Weighted Average Exercise Price
Outstanding at March 31, 2020	$ 11.67
Granted	0
Exercised	0
Forfeited	11.18
Outstanding at March 31, 2021	11.73	$ 11.67
Exercisable at March 31, 2021	$ 11.73
Weighted Average Remaining Contractual Term
Outstanding at March 31	2 years 1 month 2 days	3 years 1 month 17 days
Exercisable at March 31, 2021	2 years 1 month 2 days

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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