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Noncash Share-based Compensation Awards outstanding (Details) - shares shares in Thousands | Sep. 30, 2021 | Dec. 31, 2020
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Restricted Stock Unit - time based [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 1,822 | 1,802
Performance Shares [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 140 | 162
Stock Appreciation Rights (SARs) [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 0 | 28
Market Share Units (MSUs) [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 126 | 111

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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 equity instruments other than options outstanding, including both vested and non-vested instruments. + 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 (c)(1)(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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