Stock Options - Summary of Information About Options Outstanding (Details)	12 Months Ended
Mar. 31, 2019 $ / shares shares
Range of Exercise Prices lower	$ 5.98
Range of Exercise Prices upper	$ 7.00
Number of Options \| shares	185,700
Weighted Average Exercise Price Per Share	$ 6.18
Weighted Average Remaining Contract Life in Years	4 years 8 months 5 days
Range One [Member]
Range of Exercise Prices lower	$ 4.84
Range of Exercise Prices upper	$ 5.97
Number of Options \| shares	40,000
Weighted Average Exercise Price Per Share	$ 4.84
Range Two [Member]
Range of Exercise Prices lower	5.98
Range of Exercise Prices upper	$ 6.26
Number of Options \| shares	40,000
Weighted Average Exercise Price Per Share	$ 6.00
Range Three [Member]
Range of Exercise Prices lower	6.26
Range of Exercise Prices upper	$ 6.50
Number of Options \| shares	25,700
Weighted Average Exercise Price Per Share	$ 6.29
Range Four [Member]
Range of Exercise Prices lower	6.51
Range of Exercise Prices upper	$ 6.80
Number of Options \| shares	40,000
Weighted Average Exercise Price Per Share	$ 6.80
Range Five [Member]
Range of Exercise Prices lower	6.81
Range of Exercise Prices upper	$ 7.00
Number of Options \| shares	40,000
Weighted Average Exercise Price Per Share	$ 7.00

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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