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Stock-Based Compensation (Tables) | 3 Months Ended
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Mar. 31, 2019
Stock-Based Compensation [Abstract] |
Disclosure of restricted stock award activity | The following tables summarize our restricted stock award activity for the three months ended March 31, 2019 and 2018.
| Three Months Ended March 31, 2019
| Number of Shares of Restricted Stock Awards (in thousands) |  | Weighted Average Grant Date Fair Value
Unvested at beginning of period | 26.5 |  |  | $ | 21.31 |
Granted | 12.5 |  |  | 20.04 |
Vested | (18.5 | ) |  | 21.09 |
Forfeited | (0.5 | ) |  | 17.11 |
Outstanding (unvested) at end of period | 20.0 |  |  | $ | 20.82 |
| Three Months Ended March 31, 2018
| Number of Shares of Restricted Stock Awards (in thousands) |  | Weighted Average Grant Date Fair Value
Unvested at beginning of period | 53.7 |  |  | $ | 21.82 |
Granted | — |  |  | — |
Vested | (13.5 | ) |  | 24.86 |
Forfeited | — |  |  | — |
Outstanding (unvested) at end of period | 40.2 |  |  | $ | 20.79 |

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- Definition Stock-Based Compensation [Abstract] + References No definition available. + Details
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- Definition Tabular disclosure of components of a stock option or other award plan under which equity-based compensation is awarded to employees, typically comprised of the amount of unearned compensation (deferred compensation cost), compensation expense, and changes in the quantity and fair value of the shares (or other type of equity) granted, exercised, forfeited, and issued and outstanding pertaining to that plan. Disclosure may also include nature and general terms of such arrangements that existed during the period and potential effects of those arrangements on shareholders, effect of compensation cost arising from equity-based payment arrangements on the income statement, method of estimating the fair value of the goods or services received, or the fair value of the equity instruments granted, during the period, cash flow effects resulting from equity-based payment arrangements and, for registrants that accelerate vesting of out of the money share options, reasons for the decision to accelerate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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