DEBT (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
DebtInstrumentLineItems
Current portion of long-term debt and short-term debt	$ 1,334	$ 128,225
Long-term debt	958,604	751,990
Carrying Reported Amount Fair Value Disclosure [Member]
DebtInstrumentLineItems
Long-term Debt	959,938	880,215
Current portion of long-term debt and short-term debt	1,334	128,225
Long-term debt	958,604	751,990
Carrying Reported Amount Fair Value Disclosure [Member] | Industrial Revenue Bond [Member]
DebtInstrumentLineItems
Long-term Debt	8,400	8,400
Carrying Reported Amount Fair Value Disclosure [Member] | Revolving Credit Facility [Member]
DebtInstrumentLineItems
Long-term Debt	50,000	286,800
Carrying Reported Amount Fair Value Disclosure [Member] | Senior Notes Five Seventy Four [Member]
DebtInstrumentLineItems
Long-term Debt	0	125,011
Carrying Reported Amount Fair Value Disclosure [Member] | Senior Notes Five Fifty One [Member]
DebtInstrumentLineItems
Long-term Debt	150,000	150,000
Carrying Reported Amount Fair Value Disclosure [Member] | Senior Notes Three Eighty Four [Member]
DebtInstrumentLineItems
Long-term Debt	98,632	100,677
Carrying Reported Amount Fair Value Disclosure [Member] | Senior Notes Three Seventy [Member]
DebtInstrumentLineItems
Long-term Debt	225,000	0
Carrying Reported Amount Fair Value Disclosure [Member] | Senior Notes Three Eighty Five [Member]
DebtInstrumentLineItems
Long-term Debt	88,555	0
Carrying Reported Amount Fair Value Disclosure [Member] | Senior Notes Four Twenty Four [Member]
DebtInstrumentLineItems
Long-term Debt	173,557	198,581
Carrying Reported Amount Fair Value Disclosure [Member] | Senior Notes Four Zero Five [Member]
DebtInstrumentLineItems
Long-term Debt	64,411	0
Carrying Reported Amount Fair Value Disclosure [Member] | Senior Notes Four Eleven [Member]
DebtInstrumentLineItems
Long-term Debt	100,000	0
Carrying Reported Amount Fair Value Disclosure [Member] | Other Debt Obligations [Member]
DebtInstrumentLineItems
Long-term Debt	1,383	10,746
Estimate Of Fair Value Fair Value Disclosure [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	946,389	901,893
Current portion of long-term debt and short-term debt	1,334	128,225
Long-term debt	945,055	773,668
Estimate Of Fair Value Fair Value Disclosure [Member] | Industrial Revenue Bond [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	8,400	8,400
Estimate Of Fair Value Fair Value Disclosure [Member] | Revolving Credit Facility [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	50,000	286,800
Estimate Of Fair Value Fair Value Disclosure [Member] | Senior Notes Five Seventy Four [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	0	128,198
Estimate Of Fair Value Fair Value Disclosure [Member] | Senior Notes Five Fifty One [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	163,059	168,491
Estimate Of Fair Value Fair Value Disclosure [Member] | Senior Notes Three Eighty Four [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	98,632	100,677
Estimate Of Fair Value Fair Value Disclosure [Member] | Senior Notes Three Seventy [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	209,140	0
Estimate Of Fair Value Fair Value Disclosure [Member] | Senior Notes Three Eighty Five [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	88,555	0
Estimate Of Fair Value Fair Value Disclosure [Member] | Senior Notes Four Twenty Four [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	173,557	198,581
Estimate Of Fair Value Fair Value Disclosure [Member] | Senior Notes Four Zero Five [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	64,411	0
Estimate Of Fair Value Fair Value Disclosure [Member] | Senior Notes Four Eleven [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	89,252	0
Estimate Of Fair Value Fair Value Disclosure [Member] | Other Debt Obligations [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	$ 1,383	$ 10,746