Net Sales by Product Line (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting Information [Line Items]
Net sales	$ 47,150	$ 61,360	$ 67,866	$ 74,614	$ 62,168	$ 67,299	$ 63,318	$ 59,811	$ 250,990	$ 252,596	$ 189,423
Stainless Steel
Segment Reporting Information [Line Items]
Net sales									195,315	202,000	142,302
Tool Steel
Segment Reporting Information [Line Items]
Net sales									20,420	21,963	26,196
High Strength Low Alloy Steel
Segment Reporting Information [Line Items]
Net sales									21,897	17,532	10,310
High Temperature Alloy Steel
Segment Reporting Information [Line Items]
Net sales									7,787	6,809	5,853
Conversion Services
Segment Reporting Information [Line Items]
Net sales									4,868	3,905	2,719
Other
Segment Reporting Information [Line Items]
Net sales									$ 703	$ 387	$ 2,043