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Stock-Based Compensation (Tables) | 3 Months Ended
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Mar. 31, 2021
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, 2021 and 2020.
| Three Months Ended March 31, 2021
| Number of Shares of Restricted Stock Awards (in thousands) |  | Weighted Average Grant Date Fair Value
Unvested at beginning of period | 59.7 |  |  | $ | 20.29 |
Granted | 19.3 |  |  | 18.69 |
Vested | (25.3) |  |  | 19.78 |
Forfeited | — |  |  | — |
Outstanding (unvested) at end of period | 53.7 |  |  | $ | 19.95 |
| Three Months Ended March 31, 2020
| Number of Shares of Restricted Stock Awards (in thousands) |  | Weighted Average Grant Date Fair Value
Unvested at beginning of period | 52.1 |  |  | $ | 20.55 |
Granted | 60.2 |  |  | 20.84 |
Vested | (38.0) |  |  | 20.86 |
Forfeited | (0.5) |  |  | 19.32 |
Outstanding (unvested) at end of period | 73.8 |  |  | $ | 20.66 |

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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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