Adoption of ASC 606 - Summary of Impact of Adoption of Accounting Standards (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Net sales	$ 79,781	$ 92,390	$ 283,430	$ 338,587
Cost of sales	89,523	99,675	280,006	322,917
Gross profit (loss)	(9,742)	(7,285)	3,424	15,670
Selling, general and administrative expense	9,080	7,975	25,780	26,752
Operating loss	(16,557)	$ (15,363)	(20,542)	$ (13,340)
Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Net sales	79,781		283,430
Cost of sales	89,523		280,006
Gross profit (loss)	(9,742)		3,424
Selling, general and administrative expense	9,080		25,780
Operating loss	(16,557)		(20,542)
Accounting Standards Update 2014-09 [Member] \| Balances without adoption of 606 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Net sales	95,560		332,602
Cost of sales	105,157		328,727
Gross profit (loss)	(9,597)		3,875
Selling, general and administrative expense	9,225		26,231
Operating loss	(16,557)		(20,542)
Accounting Standards Update 2014-09 [Member] \| Effect of Change Higher/(Lower) [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Net sales	(15,779)		(49,172)
Cost of sales	(15,634)		(48,721)
Gross profit (loss)	(145)		(451)
Selling, general and administrative expense	$ (145)		$ (451)

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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