Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common stock [Member]	Treasury stock [Member]	Capital in excess of stated value [Member]	Retained Earnings [Member]	Accumulated other comprehensive loss [Member]
Beginning balance at Mar. 31, 2016	$ 123,473	$ 9,482	$ (2,600)	$ (7,645)	$ 124,413	$ (177)
Beginning balance (in shares) at Mar. 31, 2016		31,607	(8,664)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation - equity-classified awards	2,427			2,427
Restricted shares issued, net	0		$ 83	(83)
Restricted shares issued (in shares)			277
Shares issued upon exercise of stock options and SSARs	0		$ 10	(10)
Shares issued upon exercise of stock options and SSARs (in shares)			33
Shares withheld for taxes upon exercise of stock options, SSARs or vesting of restricted shares	(483)		$ (12)	(471)
Shares withheld for taxes upon exercise of stock options, SSARs or vesting of restricted shares (in shares)			(43)
Net loss	(11,721)				(11,721)
Unrealized translation adjustment	(27)					(27)
Ending balance at Mar. 31, 2017	113,669	$ 9,482	$ (2,519)	(5,782)	112,692	(204)
Ending balance (in shares) at Mar. 31, 2017		31,607	(8,397)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation - equity-classified awards	4,463			4,463
Restricted shares issued, net	0		$ 64	(64)
Restricted shares issued (in shares)			213
Shares issued upon exercise of stock options and SSARs	0		$ 2	(2)
Shares issued upon exercise of stock options and SSARs (in shares)			8
Shares withheld for taxes upon exercise of stock options, SSARs or vesting of restricted shares	(1,300)		$ (33)	(1,267)
Shares withheld for taxes upon exercise of stock options, SSARs or vesting of restricted shares (in shares)			(107)
Net loss	(8,350)				(8,350)
Unrealized translation adjustment	(51)					(51)
Ending balance at Mar. 31, 2018	108,431	$ 9,482	$ (2,486)	(1,911)	103,601	(255)
Ending balance (in shares) at Mar. 31, 2018		31,607	(8,283)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation - equity-classified awards	3,971			3,971
Restricted shares issued, net	0		$ 54	(54)
Restricted shares issued (in shares)			180
Shares issued upon exercise of stock options and SSARs	0		$ 18	(18)
Shares issued upon exercise of stock options and SSARs (in shares)			60
Shares withheld for taxes upon exercise of stock options, SSARs or vesting of restricted shares	(1,226)		$ (19)	(1,207)
Shares withheld for taxes upon exercise of stock options, SSARs or vesting of restricted shares (in shares)			(62)
Net loss	(13,164)
Unrealized translation adjustment	(4)					(4)
Ending balance at Mar. 31, 2019	$ 100,622	$ 9,482	$ (2,433)	$ 781	$ 93,051	$ (259)
Ending balance (in shares) at Mar. 31, 2019		31,607	(8,105)