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Stockholders' Equity - Narratives (Details) - USD ($) $ / shares in Units, $ in Millions | Aug. 13, 2018 | Jun. 29, 2018 | Apr. 26, 2018 | Apr. 23, 2018 | Apr. 19, 2018 | Apr. 12, 2018 | Sep. 30, 2018
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Class of Stock [Line Items] |  |  |  |  |  |  |
Stockholders' Equity Note, Stock Split |  |  |  |  |  | 3022259.23 |
Dividends, Cash |  | $ 19.5 |  |  |  |  |
Common stock dividend declared (usd per share) |  |  |  | $ 0.0645 |  |  |
Common stock dividend declared, prorated quarterly (usd per share) |  |  |  | 0.085 |  |  |
Common stock dividend declared, annualized (usd per share) |  |  |  | $ 0.34 |  |  |
Common Stock |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Shares issued (shares) |  |  | 3,097,525 |  |  |  |
Shares issued (usd per share) |  |  | $ 15 |  |  |  |
IPO |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Percentage of ownership sold in transaction |  |  |  | 11.60% |  |  |
Offering costs |  |  |  |  |  |  | $ 5.1
IPO | Common Stock |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Shares issued in IPO (shares) | 23,000,000 |  | 38,097,525 | 35,000,000 |  |  |
Sale price (usd per share) |  |  |  | $ 15 |  |  |
Brookfield |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Dividends, Cash |  |  |  |  | $ 160.0 |  |
Brookfield | Maximum |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Leverage ratio |  |  |  |  | 175.00% |  |

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