DEBT (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
DebtInstrumentLineItems
Current portion of long-term debt and short-term debt	$ 128,225	$ 2,502
Long-term debt	751,990	583,928
Estimate Of Fair Value Fair Value Disclosure [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	901,893	626,110
Current portion of long-term debt and short-term debt	128,225	2,502
Long-term debt	773,668	623,608
Estimate Of Fair Value Fair Value Disclosure [Member] \| Industrial Revenue Bond [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	8,400	9,004
Estimate Of Fair Value Fair Value Disclosure [Member] \| RevolvingCreditFacilityMember
DebtInstrumentLineItems
Long Term Debt Fair Value	286,800	0
Estimate Of Fair Value Fair Value Disclosure [Member] \| Senior Notes Five Seventy Four [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	128,198	134,982
Estimate Of Fair Value Fair Value Disclosure [Member] \| Senior Notes Five Fifty One [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	168,491	172,871
Estimate Of Fair Value Fair Value Disclosure [Member] \| Senior Notes Three Eighty Four [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	100,677	101,886
Estimate Of Fair Value Fair Value Disclosure [Member] \| Senior Notes Four Twenty Four [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	198,581	204,965
Estimate Of Fair Value Fair Value Disclosure [Member] \| Other Debt Obligations [Member]
DebtInstrumentLineItems
Long Term Debt Fair Value	10,746	2,402
Carrying Reported Amount Fair Value Disclosure [Member]
DebtInstrumentLineItems
Long-term Debt	880,215	586,430
Current portion of long-term debt and short-term debt	128,225	2,502
Long-term debt	751,990	583,928
Carrying Reported Amount Fair Value Disclosure [Member] \| Industrial Revenue Bond [Member]
DebtInstrumentLineItems
Long-term Debt	8,400	9,004
Carrying Reported Amount Fair Value Disclosure [Member] \| RevolvingCreditFacilityMember
DebtInstrumentLineItems
Long-term Debt	286,800	0
Carrying Reported Amount Fair Value Disclosure [Member] \| Senior Notes Five Seventy Four [Member]
DebtInstrumentLineItems
Long-term Debt	125,011	125,024
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	100,677	100,000
Carrying Reported Amount Fair Value Disclosure [Member] \| Senior Notes Four Twenty Four [Member]
DebtInstrumentLineItems
Long-term Debt	198,581	200,000
Carrying Reported Amount Fair Value Disclosure [Member] \| Other Debt Obligations [Member]
DebtInstrumentLineItems
Long-term Debt	$ 10,746	$ 2,402

Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Article 5

+ Details

Name:	us-gaap_DebtCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant