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Stockholders' Equity - Narratives (Details) - USD ($) $ / shares in Units, $ in Millions |  |  |  |  |  | 2 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 13, 2018 | Jun. 29, 2018 | Apr. 26, 2018 | Apr. 23, 2018 | Apr. 12, 2018 | Jun. 30, 2018 | Dec. 31, 2018 | Sep. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2018 | Apr. 19, 2018 | Dec. 31, 2017
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Stock Splits |  |  |  |  | 3,022,259.23 |  |  |  |  |  |  |
Dividends Payable |  |  |  |  |  |  |  |  |  |  | $ 160.0 |
Stock Issued During Period, Value, New Issues |  |  | 3,097,525 | 35,000,000 |  |  |  |  |  |  |  |
Shares, Issued |  |  |  |  |  |  |  |  |  |  |  | 38,097,525
Sale of Stock, Price Per Share |  |  | $ 15 | $ 15 |  |  |  |  |  |  |  |
Offering Costs |  |  |  |  |  |  |  |  |  | $ 5.1 |  |
Common Stock, Dividends, Per Share, Declared |  |  |  |  |  |  | $ 0.85 | $ 0.85 | $ 0.0645 |  |  |
Dividends |  | $ 19.5 |  |  |  |  |  |  |  |  |  |
Pro rated Dividends |  |  |  |  |  | $ 0.085 |  |  |  |  |  |
Common Stock, Dividends, Per Share, Declared, Annualized |  |  |  |  |  | $ 0.34 |  |  |  |  |  |
Special Dividend |  |  |  |  |  |  | $ 0.70 |  |  | $ 0.70 |  |
Stock Repurchased During Period, Shares | 11,688,311 |  |  |  |  |  |  |  |  |  |  |
Brookfield [Member] |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Stock Splits | 23,000,000 |  |  |  |  |  |  |  |  |  |  |
Sale of Stock, Price Per Share | $ 20.00 |  |  |  |  |  |  |  |  |  |  |

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