Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Retained Earnings
Balance at Mar. 31, 2017	$ 108,860	$ 33,889	$ (70,459)	$ 145,430
Balance (in shares) at Mar. 31, 2017		7,810
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(1,098)			(1,098)
Issuance of common stock under stock options	458	$ 458
Issuance of common stock under stock options (in shares)		91
Forfeitures of restricted share awards		(6)
Share-based compensation	217	$ 217
Balance at Mar. 31, 2018	108,437	$ 34,564	(70,459)	144,332
Balance (in shares) at Mar. 31, 2018		7,895
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(3,648)			(3,648)
Issuance of common stock under stock options	16	$ 16
Issuance of common stock under stock options (in shares)		12
Grants of restricted share awards, net of forfeitures		3
Share-based compensation	80	$ 80
Balance at Mar. 31, 2019	$ 104,885	$ 34,660	$ (70,459)	$ 140,684
Balance (in shares) at Mar. 31, 2019		7,910