Acquisitions and Disposals - Summary of Operating Results for Company's Discontinued Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Discontinued Operations and Disposal Groups [Abstract]
Net sales		$ 24,495	$ 22,225	$ 86,553
Cost of sales	(46)	26,937	24,331	90,252
Gross profit (loss)	46	(2,442)	(2,106)	(3,699)
Selling, general and administrative expense		416	396	1,117
Operating income (loss)	46	(2,858)	(2,502)	(4,816)
Interest income		47		47
Interest expense		(84)	(99)	(265)
Loss on sale of business	(1,414)		(13,497)
Loss before income taxes	(1,368)	(2,895)	(16,098)	(5,034)
Income tax benefit	(531)	(1,177)	(4,378)	(1,860)
Loss on discontinued operations	$ (837)	$ (1,718)	$ (11,720)	$ (3,174)

Disposal Group Including Discontinued Operation Cost Of Goods Sold Refunded

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Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Overall income (loss) from a disposal group that is classified as a component of the entity, before income tax, reported as a separate component of income before extraordinary items. Includes the following (before income tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Amount of general and administrative expense attributable to disposal group.

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Amount of gross profit attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of interest expense allocated to disposal group, including a discontinued operation.

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Amount of operating income or loss attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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