Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Shares [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Deficit [Member]
Beginning balance at Dec. 31, 2017	$ 93,752	$ 18,547	$ 209,253	$ (14,541)	$ (119,507)
Stockholders' Equity [Roll Forward]
Net income	(5,687)	0	0	0	(5,687)
Foreign currency translation adjustment	(1,194)	0	0	(1,194)	0
Shares issued under incentive plans, net of shares withheld for tax	2,379	170	2,209	0	0
Stock compensation expense	3,919	0	3,919	0	0
Pension liability, net of tax	201	0	0	201	0
Shares issued in public offering, netof equity issuance costs	79,522	2,806	76,716	0	0
Declared dividends	(13,835)	0	0	0	(13,835)
Ending balance at Sep. 30, 2018	159,057	21,523	292,097	(15,849)	(138,714)
Beginning balance at Jun. 30, 2018	181,261	21,430	289,088	(16,498)	(112,759)
Stockholders' Equity [Roll Forward]
Net income	(21,139)	0	0	0	(21,139)
Foreign currency translation adjustment	649	0	0	649	0
Shares issued under incentive plans, net of shares withheld for tax	1,875	93	1,782	0	0
Stock compensation expense	1,227	0	1,227	0	0
Declared dividends	(4,816)	0	0	0	(4,816)
Ending balance at Sep. 30, 2018	159,057	21,523	292,097	(15,849)	(138,714)
Stockholders' Equity [Roll Forward]
Adoption of ASU | ASU 2018-02 [Member]	0	0	0	(315)	315
Beginning balance at Dec. 31, 2018	154,638	21,547	292,558	(18,280)	(141,187)
Stockholders' Equity [Roll Forward]
Net income	18,595	0	0	0	18,595
Foreign currency translation adjustment	1,069	0	0	1,069	0
Shares issued under incentive plans, net of shares withheld for tax	(230)	116	(346)	0	0
Stock compensation expense	3,348	0	3,348	0	0
Declared dividends	(14,505)	0	0	0	(14,505)
Ending balance at Sep. 30, 2019	163,820	21,663	295,560	(17,211)	(136,192)
Beginning balance at Jun. 30, 2019	162,410	21,646	294,066	(16,745)	(136,557)
Stockholders' Equity [Roll Forward]
Net income	5,219	0	0	0	5,219
Foreign currency translation adjustment	(466)	0	0	(466)	0
Shares issued under incentive plans, net of shares withheld for tax	383	17	366	0	0
Stock compensation expense	1,128	0	1,128	0	0
Declared dividends	(4,854)	0	0	0	(4,854)
Ending balance at Sep. 30, 2019	163,820	21,663	295,560	(17,211)	(136,192)
Stockholders' Equity [Roll Forward]
Adoption of ASU | ASU 2016-02 [Member]	$ 905	$ 0	$ 0	$ 0	$ 905