EMPLOYEE BENEFIT PLANS, Plan Asset Allocations (Details) (Pension Benefits [Member])	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Pension Benefits [Member]
Target allocation [Abstract]
Domestic equity securities (in hundredths)	60.00%	60.00%
International equity securities (in hundredths)	10.00%	10.00%
Debt securities (in hundredths)	15.00%	15.00%
Real estate (in hundredths)	15.00%	15.00%
Other and cash (in hundredths)	0.00%	0.00%
Total (in hundredths)	100.00%	100.00%
Weighted-average allocations [Abstract]
Domestic equity securities (in hundredths)	62.00%	61.00%
International equity securities (in hundredths)	11.00%	11.00%
Debt securities (in hundredths)	16.00%	15.00%
Real estate (in hundredths)	4.00%	8.00%
Other and cash (in hundredths)	7.00%	5.00%
Total (in hundredths)	100.00%	100.00%
Basis used to determine long-term rate of return assumption [Abstract]
One-year pension returns (losses) (in hundredths)	15.30%
Three-year pension returns (losses) (in hundredths)	(3.50%)
Five-year pension returns (losses) (in hundredths)	3.50%
Long-term average return since plan inception (in hundredths)	8.60%
Long-term rate of return assumption (in hundredths)	8.25%	8.50%	8.50%

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The percentage of the fair value of domestic equity securities to the fair value of total plan assets held as of the measurement date.

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The percentage of the fair value of international equity securities to the fair value of total plan assets held as of the measurement date.

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No definition available.

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Target allocation percentage of investments in total securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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No definition available.

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Target allocation percentage of investments in domestic equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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No definition available.

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Target allocation percentage of investments in international equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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No definition available.

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The percentage of five-year pension returns (losses) on plan assets.

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No definition available.

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The approximate percentage of pension returns (losses) on plan assets, since plan inception.

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No definition available.

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The percentage of one-year pension returns (losses) on plan assets.

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No definition available.

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The percentage of three-year pension returns (losses) on plan assets.

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No definition available.

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An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

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-Glossary Expected Long-Term Rate of Return on Plan Assets

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The percentage of the fair value of debt securities to the fair value of total plan assets held as of the measurement date.

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The percentage of the fair value of investments other than debt securities, equity securities, and real estate to the fair value of total plan assets held as of the measurement date.

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The percentage of the fair value of real estate to the fair value of total plan assets held as of the measurement date.

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Target allocation percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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Target allocation percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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Target allocation percentage of investments in real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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The aggregate percentage of the fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of total plan assets held as of the measurement date.

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