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Stock-based Compensation - Stock Options (Details) - shares | 3 Months Ended | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2020
Share-based compensation |  |
Number of shares, Granted | 0 |
Stock Options |  |
Share-based compensation |  |
Minimum age required for employees to qualify for immediate vesting of award |  | 55 years
Threshold years required for retirement age |  | 70 years
Number of shares, Granted |  | 187,811
Stock Options | Employees |  |
Share-based compensation |  |
Vesting period |  | 3 years
Stock Options | Directors |  |
Share-based compensation |  |
Vesting period |  | 1 year

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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition Minimum age required for employees to qualify for immediate vesting of award. + References No definition available. + Details
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- Definition Threshold years required for retirement age (defined as employees that are a minimum of 55 years of age and the sum of their age plus years of full-time employment with the Company). + References No definition available. + Details
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