RETIREMENT PLAN AND POST-RETIREMENT BENEFITS, Assumptions (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Actuarial assumptions used to determine benefit obligations [Abstract]
Discount rate (in hundredths)	4.91%	5.09%
Rate of compensation increase (in hundredths)	4.00%	4.00%
Initial health care cost trend rate (in hundredths)	8.00%	8.00%
Ultimate health care cost trend rate (in hundredths)	4.75%	4.75%
Number of years to ultimate trend rate (in years)	7	8
Actuarial assumptions used to determine net periodic benefit costs [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	5.09%	5.79%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase	4.00%	4.50%
Initial health care cost trend rate (in hundredths)	8.00%	8.00%
Ultimate health care cost trend rate (in hundredths)	4.75%	5.00%
Number of years to ultimate trend rate (in years)	8	7
Effect of one-percentage-point change in assumed health care cost trend rates [Abstract]
Effect of one percentage point increase on the postretirement benefit obligation	$ 6,446
Effect of one percentage point increase on total of service and interest cost components	696
Effect of one percentage point decrease on the postretirement benefit obligation	(5,251)
Effect of one percentage point decrease on total of service and interest cost components	$ (542)
Maximum [Member]
Actuarial assumptions used to determine net periodic benefit costs [Abstract]
Percentile yields on portfolio of high quality AA bonds (in hundredths)	90.00%
Minimum [Member]
Actuarial assumptions used to determine net periodic benefit costs [Abstract]
Portfolio high quality Aa bonds matched to, minimum (number of bonds)	300
Percentile yields on portfolio of high quality AA bonds (in hundredths)	10.00%
Pension Benefits [Member]
Actuarial assumptions used to determine net periodic benefit costs [Abstract]
Expected long-term rate of return on plan assets, range minimum (in hundredths)	6.75%	6.75%
Other Post-Retirement Benefits [Member]
Actuarial assumptions used to determine benefit obligations [Abstract]
Discount rate (in hundredths)	5.09%	5.20%
Actuarial assumptions used to determine net periodic benefit costs [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	5.20%	5.75%
Other Post-Retirement Benefits [Member] \| Maximum [Member]
Actuarial assumptions used to determine net periodic benefit costs [Abstract]
Expected long-term rate of return on plan assets, range minimum (in hundredths)	7.10%	7.10%
Other Post-Retirement Benefits [Member] \| Minimum [Member]
Actuarial assumptions used to determine net periodic benefit costs [Abstract]
Expected long-term rate of return on plan assets, range minimum (in hundredths)	6.75%	6.75%

The ultimate trend rate for health care costs, as used in calculating net periodic benefits costs.

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The assumed number of years until the ultimate health care cost trend rate is expected to be reached.

+ References

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The assumed number of years it will take to reach the ultimate health care cost trend rate as used in calculation of net periodic benefit costs.

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The assumed health care cost trend rate for the next year used to measure the net periodic benefits costs covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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The minimum number of high quality AA bonds with yields within the 10th to 90th percentiles of these bonds, to which the Company's projected benefit payments were matched to.

+ References

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The percentile of the high quality AA bond yields to which the Company's benefit payments were matched to.

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The interest rate used to adjust for the time value of money for the plan.

+ References

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- Definition

Expected rate of compensation increases (for pay-related plans).

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The interest rate used to adjust for the time value of money.

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- Definition

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

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

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Expected rate of compensation increases (for pay-related plans).

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The effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage- point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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-Glossary Health Care Cost Trend Rate

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The ultimate trend rate for health care costs.

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