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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Mar. 31, 2019 | Jun. 30, 2018 | Mar. 31, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Stockholders' Equity Note [Abstract] |  |  |  |  |  |
Dividends |  |  |  |  | $ 24.7 | $ 16.8
Aggregate number of shares repurchased during the period (in shares) |  |  |  |  | 315,369 |
Shares repurchased under the program (in shares) |  |  |  |  | 88,210 |
Authorized to repurchased additional shares under repurchase program (in shares) | 1,522,945 |  |  |  | 1,522,945 |
Shares withheld for tax withholding obligations for the vesting of restricted stock awards (in shares) |  |  |  |  | 227,159 |
Dividends declared per share of common stock (in dollars per share) | $ 0.30 | $ 0.30 | $ 0.20 | $ 0.20 |  |

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