Consolidated Statements Of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Dec. 31, 2017	$ 3	$ 485,285	$ (310,390)	$ (12,415)	$ 499	$ 162,982
Balance, shares at Dec. 31, 2017	32,917			(2,875)
Net income (loss)			403			403
Other comprehensive income (loss)					714	714
Stock compensation expense		499				499
Balance at Mar. 31, 2018	$ 3	485,784	(309,987)	$ (12,415)	1,213	164,598
Balance, shares at Mar. 31, 2018	32,917			(2,875)
Balance at Dec. 31, 2017	$ 3	485,285	(310,390)	$ (12,415)	499	162,982
Balance, shares at Dec. 31, 2017	32,917			(2,875)
Net income (loss)						3,753
Other comprehensive income (loss)						175
Stock compensation expense						2,067
Balance at Sep. 30, 2018	$ 3	487,819	(307,378)	$ (17,124)	674	163,994
Balance, shares at Sep. 30, 2018	33,244			(3,394)
Balance at Mar. 31, 2018	$ 3	485,784	(309,987)	$ (12,415)	1,213	164,598
Balance, shares at Mar. 31, 2018	32,917			(2,875)
Net income (loss)			(777)			(777)
Other comprehensive income (loss)					(292)	(292)
Purchase of treasury stock, value				$ (217)		(217)
Stock compensation expense		656				656
Balance at Jun. 30, 2018	$ 3	486,440	(310,764)	$ (12,632)	921	163,968
Balance, shares at Jun. 30, 2018	32,917			(2,875)
Net income (loss)			4,127			4,127
Other comprehensive income (loss)					(247)	(247)
Cash dividends ($0.025 per share)			(741)			(741)
Purchase of treasury stock, value				$ (4,492)		(4,492)
Purchase of treasury stock, shares				(519)
Stock compensation expense		912				912
Proceeds from exercise of options		467				467
Proceeds from exercise of options, shares	327
Balance at Sep. 30, 2018	$ 3	487,819	(307,378)	$ (17,124)	674	163,994
Balance, shares at Sep. 30, 2018	33,244			(3,394)
Balance at Dec. 31, 2018	$ 3	488,404	(304,577)	$ (18,102)	477	166,205
Balance, shares at Dec. 31, 2018	33,244			(3,496)
Net income (loss)			3,787			3,787
Other comprehensive income (loss)					(462)	(462)
Cash dividends ($0.025 per share)			(746)			(746)
Stock compensation expense		785				785
Balance at Mar. 31, 2019	$ 3	489,189	(301,536)	$ (18,102)	15	169,569
Balance, shares at Mar. 31, 2019	33,244			(3,496)
Balance at Dec. 31, 2018	$ 3	488,404	(304,577)	$ (18,102)	477	166,205
Balance, shares at Dec. 31, 2018	33,244			(3,496)
Net income (loss)						6,585
Other comprehensive income (loss)						(698)
Stock compensation expense						2,246
Balance at Sep. 30, 2019	$ 3	491,546	(300,235)	$ (22,269)	(221)	168,824
Balance, shares at Sep. 30, 2019	33,605			(3,855)
Balance at Mar. 31, 2019	$ 3	489,189	(301,536)	$ (18,102)	15	169,569
Balance, shares at Mar. 31, 2019	33,244			(3,496)
Net income (loss)			(694)			(694)
Other comprehensive income (loss)					(269)	(269)
Cash dividends ($0.025 per share)			(748)			(748)
Purchase of treasury stock, value				$ (1,505)		(1,505)
Purchase of treasury stock, shares				(116)
Stock compensation expense		783				783
Proceeds from exercise of options		804				804
Proceeds from exercise of options, shares	351
Balance at Jun. 30, 2019	$ 3	490,776	(302,978)	$ (19,607)	(254)	167,940
Balance, shares at Jun. 30, 2019	33,595			(3,612)
Net income (loss)			3,492			3,492
Other comprehensive income (loss)					33	33
Cash dividends ($0.025 per share)			(749)			(749)
Purchase of treasury stock, value				$ (2,662)		(2,662)
Purchase of treasury stock, shares				(243)
Stock compensation expense		678				678
Proceeds from exercise of options		92				92
Proceeds from exercise of options, shares	10
Balance at Sep. 30, 2019	$ 3	$ 491,546	$ (300,235)	$ (22,269)	$ (221)	$ 168,824
Balance, shares at Sep. 30, 2019	33,605			(3,855)