Accumulated Other Comprehensive Loss - Line Items Affected on Condensed Consolidated Statements of Operations for Components Reclassified from Accumulated Other Comprehensive Loss (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
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Costs of products sold (excluding depreciation)	$ 53,244	$ 48,177	$ 158,715	$ 158,577
Selling and administrative	8,950	8,979	27,424	28,135
Other income (expense)	395	532	344	1,539
Income tax provision	(178)	7,057	773	7,958
Net (loss) income	343	(12,705)	(856)	(13,937)
Depreciation	2,941	2,840	9,007	8,725
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member] | Amortization of Unrecognized Employee Benefit Costs [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Costs of products sold (excluding depreciation)	844	1,442	2,752	4,262
Selling and administrative	401	573	1,136	1,682
Other income (expense)	44	217	128	650
Total before income tax	1,289	2,232	4,016	6,594
Income tax provision	(462)	(774)	(1,404)	(2,349)
Net (loss) income	827	1,458	2,612	4,245
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member] | Realized (Gains) from Sale of Marketable Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling and administrative	(37)	(26)	(91)	(79)
Income tax provision	13	9	32	28
Net (loss) income	(24)	(17)	(59)	(51)
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member] | Realized (Gains) Losses from Settlement of Cash Flow Hedges [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before income tax	(21)	231	88	332
Income tax provision	8	(87)	(33)	(126)
Net (loss) income	(13)	144	55	206
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member] | Realized (Gains) Losses from Settlement of Cash Flow Hedges [Member] | Foreign Currency Sales Contracts [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Depreciation	(22)	0	(22)	0
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member] | Realized (Gains) Losses from Settlement of Cash Flow Hedges [Member] | Foreign Currency Purchase Contracts [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Depreciation	(6)	(6)	(20)	(20)
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member] | Realized (Gains) Losses from Settlement of Cash Flow Hedges [Member] | Futures Contracts - Copper and Aluminum [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Costs of products sold (excluding depreciation)	$ 7	$ 237	$ 130	$ 352