Gross Accounts Receivable from Significant Customers as Percentage of Total Consolidated Gross Accounts Receivable (Detail) (Accounts Receivable, Customer Concentration Risk)	Nov. 30, 2012	Feb. 29, 2012
Chrysler
Concentration Risk [Line Items]
Percentage of Consolidated Gross Accounts Receivable	19.00%	18.00%
US Steel
Concentration Risk [Line Items]
Percentage of Consolidated Gross Accounts Receivable	9.00%	12.00%
Ford
Concentration Risk [Line Items]
Percentage of Consolidated Gross Accounts Receivable	5.00%	15.00%