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INCOME TAXES (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended
--- | --- | ---
Dec. 31, 2017 | Mar. 31, 2018 | Mar. 31, 2017
Effective Income Tax Rate Reconciliation, Amount |  |  |
Statutory federal income tax, amount |  | $ 100.5 |
State income taxes net of federal tax benefit, amount |  | 29.9 |
Federal tax reform, amount |  | (15.5) |
Tax repairs, amount |  | (25.5) |
Other, amount |  | (1.1) |
Total income tax expense, amount |  | $ 88.3 | $ 213.3
Effective Income Tax Rate Reconciliation, Percent |  |  |
Statutory federal income tax, percentage |  | 21.00% | 35.00%
State income taxes net of federal tax benefit, percentage |  | 6.20% |
Federal tax reform, percentage |  | (3.20%) |
Tax repairs, percentage |  | (5.30%) |
Other, percentage |  | (0.30%) |
Total income tax expense, percentage |  | 18.40% |
Measurement period to complete accounting related to Tax Cuts and Jobs Act | 1 year |  |

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