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Stock-Based Compensation (Tables) | 6 Months Ended
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Jun. 30, 2019
Stock-Based Compensation [Abstract] |
Disclosure of restricted stock award activity | The following tables summarize our restricted stock award activity for the three and six months ended June 30, 2019 and 2018.
| Three Months Ended June 30, 2019
| Number of Shares of Restricted Stock Awards (in thousands) |  | Weighted Average Grant Date Fair Value
Unvested at beginning of period | 20.0 |  |  | $ | 20.82 |
Granted | 75.0 |  |  | 19.32 |
Vested | (36.5 | ) |  | 19.32 |
Forfeited | — |  |  | — |
Outstanding (unvested) at end of period | 58.5 |  |  | $ | 19.83 |
| Three Months Ended June 30, 2018
| Number of Shares of Restricted Stock Awards (in thousands) |  | Weighted Average Grant Date Fair Value
Unvested at beginning of period | 40.2 |  |  | $ | 20.79 |
Granted | 5.0 |  |  | 19.03 |
Vested | (8.7 | ) |  | 22.44 |
Forfeited | (1.5 | ) |  | 17.11 |
Outstanding (unvested) at end of period | 35.0 |  |  | $ | 20.29 |
| Six Months Ended June 30, 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 | 87.5 |  |  | 19.42 |
Vested | (55.0 | ) |  | 19.92 |
Forfeited | (0.5 | ) |  | 17.11 |
Outstanding (unvested) at end of period | 58.5 |  |  | $ | 19.83 |
| Six Months Ended June 30, 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 | 5.0 |  |  | 19.03 |
Vested | (22.2 | ) |  | 23.91 |
Forfeited | (1.5 | ) |  | 17.11 |
Outstanding (unvested) at end of period | 35.0 |  |  | $ | 20.29 |

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- Definition Tabular disclosure of share-based payment arrangement. + 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=116856206&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=116856206&loc=d3e5070-113901 + Details
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