Adoption of ASC 606 - Summary of Impact of Adoption of Accounting Standards (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Net sales	$ 103,199	$ 122,853	$ 203,649	$ 246,197
Cost of sales	100,126	111,513	190,483	223,242
Gross profit	3,073	11,340	13,166	22,955
Selling, general and administrative expense	8,397	8,232	16,700	18,777
Operating loss	(5,869)	$ (298)	(3,985)	$ 2,023
Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Net sales	103,199		203,649
Cost of sales	100,126		190,483
Gross profit	3,073		13,166
Selling, general and administrative expense	8,397		16,700
Operating loss	(5,869)		(3,985)
Accounting Standards Update 2014-09 [Member] \| Balances without adoption of 606 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Net sales	120,492		237,042
Cost of sales	117,264		223,570
Gross profit	3,228		13,472
Selling, general and administrative expense	8,552		17,006
Operating loss	(5,869)		(3,985)
Accounting Standards Update 2014-09 [Member] \| Effect of Change Higher/(Lower) [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Net sales	(17,293)		(33,393)
Cost of sales	(17,138)		(33,087)
Gross profit	(155)		(306)
Selling, general and administrative expense	$ (155)		$ (306)

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

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