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PENSION AND POST-RETIREMENT PLANS - ASSET ALLOCATION (Details) - plan | 12 Months Ended |
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Dec. 31, 2016 | Dec. 31, 2015
Employee benefit plans |  |
Number of single-employer defined benefit pension funded plans | 2 |
Pensions |  |
Employee benefit plans |  |
Target allocation (as a percent) | 100.00% |
Asset allocations (as a percent) | 100.00% | 100.00%
One year returns (losses) on plan assets (as a percent) | 8.30% |
Three year returns (losses) on plan assets (as a percent) | 4.00% |
Five year returns (losses) on plan assets (as a percent) | 9.40% |
Long-term average return on plan assets since inception (as a percent) | 8.30% |
Pensions | Domestic equity securities |  |
Employee benefit plans |  |
Target allocation (as a percent) | 53.00% |
Asset allocations (as a percent) | 62.00% | 62.00%
Pensions | International equity securities |  |
Employee benefit plans |  |
Target allocation (as a percent) | 15.00% |
Asset allocations (as a percent) | 13.00% | 13.00%
Pensions | Debt securities |  |
Employee benefit plans |  |
Target allocation (as a percent) | 22.00% |
Asset allocations (as a percent) | 17.00% | 18.00%
Pensions | Real estate |  |
Employee benefit plans |  |
Target allocation (as a percent) | 5.00% |
Asset allocations (as a percent) | 6.00% | 6.00%
Pensions | Other and cash |  |
Employee benefit plans |  |
Target allocation (as a percent) | 5.00% |
Asset allocations (as a percent) | 2.00% | 1.00%

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