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Incentive Plans (Tables) | 12 Months Ended
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Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of stock option award activity | The following is a summary of stock option award activity for 2018:
| Shares (in thousands) |  | Weighted Average Exercise Price Per Share |  | Weighted Average Remaining Contractual Life (in years) |  | Aggregate Intrinsic Value (in thousands)
Outstanding - December 31, 2017 | 16 |  |  | $ | 15.30 |  |  |  |  |
Granted | — |  |  | — |  |  |  |  |
Exercised | — |  |  | — |  |  |  |  |
Canceled | — |  |  | — |  |  |  |  |
Outstanding - December 31, 2018 | 16 |  |  | $ | 15.30 |  |  | 2.5 |  | $ | 1,220 |
Exercisable - December 31, 2018 | 16 |  |  | $ | 15.30 |  |  | 2.5 |  | $ | 1,220 |
Restricted Stock [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of restricted stock awards activity | The following is a summary of restricted stock award activity for 2018:
| Shares (in thousands) |  | Weighted Average Grant Date Fair Value
Non-vested - December 31, 2017 | 343 |  |  | $ | 35.29 |
Granted | 290 |  |  | 65.98 |
Vested | (14 | ) |  | 66.28 |
Canceled/Forfeited | (37 | ) |  | 41.37 |
Non-vested - December 31, 2018 | 582 |  |  | $ | 49.48 |
Long-Term Incentive Program Awards [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of restricted stock awards activity | The following is a summary of LTIP award activity, at 100% of targeted amount, for 2018:
| Number of Performance Units (in thousands) |  | Weighted Average Grant Date Fair Value
Unvested at December 31, 2017 | 570 |  |  | $ | 32.90 |
Granted | 100 |  |  | 81.51 |
Vested | (196 | ) |  | 26.40 |
Canceled | (48 | ) |  | 41.90 |
Unvested at December 31, 2018 | 426 |  |  | $ | 46.35 |

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- Definition Tabular disclosure of the changes in outstanding nonvested shares. + 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) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + 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 (d) -URI http://asc.fasb.org/extlink&oid=109197908&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 (e) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 3: 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) -URI http://asc.fasb.org/extlink&oid=109197908&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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