| **POSTRETIREMENT BENEFITS (Tables)**         | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
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| **POSTRETIREMENT BENEFITS [Abstract]**       | Â                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Schedule of defined benefit plan disclosures |    Pension benefits  Health care andother benefits    2011  2010  2011  2010 Three months ended June 30            Service cost $2.5  $2.5  $.6  $.5 Interest cost  4.1   4.0   3.0   2.9 Expected return on plan assets  (7.8)  (7.3)  -   - Recognized net actuarial loss  2.4   2.9   1.5   1.1 Amortization of prior service cost  .1   .1   .1   .1 Net benefit cost $1.3  $2.2  $5.2  $4.6                   Six months ended June 30            Service cost $5.0  $4.9  $1.2  $1.1 Interest cost  8.2   8.0   6.1   5.9 Expected return on plan assets  (15.6)  (14.5)  -   - Recognized net actuarial loss  4.8   5.9   3.0   2.1 Amortization of prior service cost  .2   .2   .1   .1 Net benefit cost $2.6  $4.5  $10.4  $9.2      |

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| - Definition
Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans.
+ References
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