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Share-Based Compensation - Long Term Incentive Plan (Details) - shares | 12 Months Ended |
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Dec. 31, 2020 | May 06, 2016
2018 Long Term Incentive and Share Award Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of shares reserved for issuance | 34,500,000 |
Shares available for issuance transferred | 17,284,108 |
2015 Long Term Incentive And Share Award Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of shares reserved for issuance | 12,900,000 |
Shares available for issuance | 555,759 |
2007 Employee Share Purchase Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares available for issuance | 2,267,676 | 4,689,777
2012 Long Term Incentive and Share Award Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Total number of shares reserved under plan | 22,301,772 |
Shares available for issuance | 502,994 |

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- Definition Total number of shares reserved under plan + References No definition available. + 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 Number of shares authorized for issuance under 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 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Other than shares newly issued, the number of additional shares issued (for example, a stock split) or canceled (for example, to correct a share issuance), during the period under the plan. + 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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