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v3.10.0.1

EQUITY (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Dividends declared per share of stock |  | $ 0.46 | $ 0.46 | $ 0.46 | $ 0.46 | $ 0.42 | $ 0.42 | $ 0.42 | $ 0.42 | $ 1.84 | $ 1.68 | $ 1.40
Preferred Stock, Shares Authorized |  | 50.0 |  |  |  |  |  |  |  | 50.0 |  |
Preferred Stock, Par or Stated Value Per Share |  | $ 0.01 |  |  |  |  |  |  |  | $ 0.01 |  |
Common stock authorized and available for issuance |  | 197.4 |  |  |  |  |  |  |  | 197.4 |  |
Stock Repurchase Program, Authorized Amount |  | $ 20 |  |  |  |  |  |  |  | $ 20 |  |
Common Stock, Dividends, Declared, Annualized Basis |  |  |  |  |  |  |  |  |  | $ 1.68 | $ 1.40 | $ 1.20
Dividend Declared [Member] |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Dividends, Per Share, Declared | $ 0.50 |  |  |  |  |  |  |  |  |  |  |
Common Stock, Dividends, Declared, Annualized Basis | $ 2.00 |  |  |  |  |  |  |  |  |  |  |

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