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Share-Based Compensation and Other Compensation Matters (Grants to Executives) (Details) - USD ($) $ in Thousands |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Jan. 01, 2020 | Jan. 01, 2019 | Jan. 01, 2018 | Jan. 01, 2017 | Mar. 01, 2016 | Dec. 31, 2020
Performance-based PIUs | Former Executive Vice President and Chief Operating Officer |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Forfeitures (in shares) |  |  |  |  |  | 73,184
Performance-based PIUs | 2019 PB PIU |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock awards granted (in shares or units) |  | 193,682 |  |  |  |
Grant Date Fair Value |  | $ 2,415 |  |  |  |
Unvested at the end of the period (in shares) |  |  |  |  |  | 156,104
Performance-based PIUs | 2020 PB PIU |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock awards granted (in shares or units) | 176,758 |  |  |  |  |
Grant Date Fair Value | $ 2,891 |  |  |  |  |
Unvested at the end of the period (in shares) |  |  |  |  |  | 141,152
Performance share units | 2016 PSU Grants |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock awards granted (in shares or units) |  |  |  |  | 26,299 |
Grant Date Fair Value |  |  |  |  | $ 1,005 |
Unvested at the end of the period (in shares) |  |  |  |  |  | 0
Performance share units | 2017 PSU Grants |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock awards granted (in shares or units) |  |  |  | 39,351 |  |
Grant Date Fair Value |  |  |  | $ 1,415 |  |
Unvested at the end of the period (in shares) |  |  |  |  |  | 0
Performance share units | 2018 PSU Grants |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock awards granted (in shares or units) |  |  | 59,110 |  |  |
Grant Date Fair Value |  |  | $ 1,890 |  |  |
Unvested at the end of the period (in shares) |  |  |  |  |  | 46,912
Performance share units | 2018 PSU Grants | Former Executive Vice President and Chief Operating Officer |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Forfeitures (in shares) |  |  |  |  |  | 12,198

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- Definition The aggregate fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References No definition available. + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + 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)(2)(i)-(ii) -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 under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event. + 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)(iv)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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