Discontinued Operations Summarized results of discontinued operations (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016		Sep. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operation, Net sales		$ 0	$ 34,105	$ 29,680		$ 101,168
Discontinued Operation, Cost of Materials		0	23,970	21,027		71,251
Discontinued Operation, Operating costs and expenses		0	8,201	7,288		25,005
Discontinued Operation, Interest expense	[1]	0	350	333		1,081
Income from discontinued operations before income taxes		0	1,584	1,032		3,831
Discontinued Operation, Income tax expense (benefit)		0	629	(3,908)	[2]	1,498
Gain (loss) on sale of discontinued operations, net of income taxes		(1,688)	0	1,306		0
Income (Loss) from Discontinued Operations, Net of Income Taxes		$ (1,688)	$ 955	$ 6,246		$ 2,333

[1] (a)Interest expense was allocated to the discontinued operation based on the debt that was required to be paid as a result of the sale of TPI.

[2] (b) Income tax benefit for the nine months ended September 30, 2016 includes $4,207 reversal of valuation allowance resulting from the sale of TPI.