Discontinued Operations - Operating Results for Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended					12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Jun. 30, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net loss	$ (3,221)	$ (130)	$ (364)	$ (132)		$ 0	$ (3,847)	$ (6,461)
Bayou Welding Works
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues						0	0	9,763
Gross profit (loss)						0	(67)	(4,255)
Operating expenses						0	(5,941)	1,973
Closure charges of welding business					$ (100)	0	0	5,019
Operating loss						0	(6,008)	(11,247)
Other income (expense)						0	(74)	0
Loss before tax benefits						0	(6,082)	(10,731)
Tax benefits						0	2,235	4,270
Net loss						$ 0	$ (3,847)	$ (6,461)