Segment Information - Reconciliation of Segment Adjusted EBITDA to Income Before Provision for Income Taxes and Equity Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Segment Information [Line Items]
Net sales	$ 461,478	$ 416,979	$ 906,440	$ 860,370
Total segment adjusted EBITDA	39,490	35,521	74,371	71,370
Corporate and Other	(8,500)	(5,550)	(14,327)	(9,429)
Loss on extinguishment of debt		(19,612)		(19,612)
Depreciation and amortization	(2,072)	(1,681)	(3,981)	(3,205)
Interest expense	(9,959)	(10,209)	(19,834)	(19,958)
Equity method investment income	(327)	(20)	(498)	(113)
Net income attributable to noncontrolling interest	61	114	159	168
Lower of cost or market adjustment to inventory	(318)		(318)
(Loss) gain on derivative contracts	(41)	(109)	(62)	1,204
Share-based compensation expense	(181)		(181)
Compensation expense-profits interest awards	(29,271)	(19,517)	(29,271)	(19,517)
(Loss) income before provision for (benefit from) income taxes and equity income	(11,118)	(21,063)	6,058	908
Olin Brass [Member]
Segment Information [Line Items]
Net sales	216,500	165,803	403,065	332,090
Total segment adjusted EBITDA	16,233	13,062	27,683	23,751
Chase [Member]
Segment Information [Line Items]
Net sales	164,697	165,922	339,179	354,609
Total segment adjusted EBITDA	18,954	17,251	37,835	37,191
Oster [Member]
Segment Information [Line Items]
Net sales	80,281	85,254	164,196	173,671
Total segment adjusted EBITDA	4,303	5,208	8,853	10,428
Intersegment Eliminations [Member]
Segment Information [Line Items]
Net sales	14,259	12,929	28,663	25,431
Intersegment Eliminations [Member] | Olin Brass [Member]
Segment Information [Line Items]
Net sales	14,210	12,754	28,548	25,107
Intersegment Eliminations [Member] | Chase [Member]
Segment Information [Line Items]
Net sales	7	156	7	302
Intersegment Eliminations [Member] | Oster [Member]
Segment Information [Line Items]
Net sales	$ 42	$ 19	$ 108	$ 22