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Share-Based Compensation and Other Compensation Matters (Details 3) - Performance share units [Member] - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  |  | 12 Months Ended
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Jan. 01, 2018 | Jan. 01, 2017 | Mar. 01, 2016 | Mar. 05, 2015 | Mar. 06, 2014 | Dec. 31, 2018
2014 PSU Grants [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock awards granted (in shares or units) |  |  |  |  | 49,103 |
Grant date fair value |  |  |  |  | $ 1,723 |
Unvested at the end of the period (in shares) |  |  |  |  |  | 0
2015 PSU Grants [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock awards granted (in shares or units) |  |  |  | 45,656 |  |
Grant date fair value |  |  |  | $ 1,678 |  |
Unvested at the end of the period (in shares) |  |  |  |  |  | 0
2016 PSU Grants [Member] |  |  |  |  |  |
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) |  |  |  |  |  | 24,850
Grant date fair value (in dollars per share) |  |  | $ 38.21 |  |  |
2017 PSU Grants [Member] |  |  |  |  |  |
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) |  |  |  |  |  | 39,351
Grant date fair value (in dollars per share) |  | $ 38.43 |  |  |  |
2018 PSU Grants [Member] |  |  |  |  |  |
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) |  |  |  |  |  | 59,110
Grant date fair value (in dollars per share) | $ 31.97 |  |  |  |  |

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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=109197908&loc=d3e5070-113901 + Details
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- Definition The weighted average 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 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=109197908&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=109197908&loc=d3e5070-113901 + Details
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