XML 63 R38.htm IDEA: XBRL DOCUMENT v2.4.0.6
Financial Assets and Liabilities Accounted For at Fair Value on Recurring Basis (Detail) (USD $)
Mar. 31, 2013
Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities $ 429,488 $ 425,151
Convertible senior notes
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities 127,822 126,918
Term loan credit agreement
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities 290,283 290,812
Industrial revenue bond
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities 2,463 2,500
Capital lease obligations
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities 8,920 4,921
Fair Value, Inputs, Level 1
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 1 | Convertible senior notes
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 1 | Term loan credit agreement
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 1 | Industrial revenue bond
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 1 | Capital lease obligations
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 2
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 483,166 466,291
Fair Value, Inputs, Level 2 | Convertible senior notes
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 183,938 165,563
Fair Value, Inputs, Level 2 | Term loan credit agreement
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 299,228 300,728
Fair Value, Inputs, Level 2 | Industrial revenue bond
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 2 | Capital lease obligations
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 3
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 11,383 7,421
Fair Value, Inputs, Level 3 | Convertible senior notes
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 3 | Term loan credit agreement
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 0 0
Fair Value, Inputs, Level 3 | Industrial revenue bond
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring 2,463 2,500
Fair Value, Inputs, Level 3 | Capital lease obligations
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Liabilities, fair value disclosure, recurring $ 8,920 $ 4,921