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Share-Based Compensation - Additional Information (Details) - shares | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | May 05, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Long-term equity incentive plan, termination date | May 05, 2030 |  |  |
Number of shares available for future issuance under share-based plan | 1,500,000 |  |  | 1,400,000
Number of shares authorized under plan | 12,000,000.0 |  |  |
Restricted Stock | Officers and Employees |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period | 4 years |  |  |
Performance Units |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period of ROIC as performance measure | 4 years |  |  |
Vesting period of TSR as performance measure | 3 years |  |  |
Percentage of ROIC as performance measure | 50.00% | 50.00% | 50.00% |
Percentage of TSR as performance measure | 50.00% | 50.00% | 50.00% |

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- Definition Share based compensation arrangement by share based payment award award vesting period performance measurement based on return on invested capital. + References No definition available. + Details
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- Definition Share based compensation arrangement by share based payment award award vesting period performance measurement based on total shareholder return. + References No definition available. + Details
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- Definition Share based compensation arrangement by share based payment award percentage of performance measurement based on return on invested capital. + References No definition available. + Details
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- Definition Share based compensation arrangement by share based payment award percentage of performance measurement based on total shareholder return. + References No definition available. + Details
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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 Date the equity-based award expires, in CCYY-MM-DD format. + 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)(2) -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 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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