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Incentive Plans (Tables) | 12 Months Ended
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Dec. 31, 2017
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 2017:
|  | Shares |  | Weighted Average Exercise Price Per Share |  | Weighted Average Remaining Contractual Life |  | Aggregate Intrinsic Value
|  | (in thousands) |  |  |  | (in years) |  | (in thousands)
Outstanding - December 31, 2016 |  | 16 |  |  | $ | 15.30 |  |  |  |  |
Granted |  | — |  |  | — |  |  |  |  |
Exercised |  | — |  |  | — |  |  |  |  |
Canceled |  | — |  |  | — |  |  |  |  |
Outstanding - December 31, 2017 |  | 16 |  |  | $ | 15.30 |  |  | 3.5 |  | $ | 657 |
Exercisable - December 31, 2017 |  | 16 |  |  | $ | 15.30 |  |  | 3.5 |  | $ | 657 |
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 2017:
|  | Shares |  | Weighted Average Grant Date Fair Value
|  | (in thousands) |  |
Non-vested - December 31, 2016 |  | 1,006 |  |  | $ | 23.09 |
Granted |  | 323 |  |  | 42.15 |
Vested |  | (952 | ) |  | 24.87 |
Canceled/Forfeited |  | (34 | ) |  | 31.24 |
Non-vested - December 31, 2017 |  | 343 |  |  | $ | 35.29 |
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 for 2017:
|  | Number of Performance Units at Target |  | Weighted Average Grant Date Fair Value |  | Maximum Shares Eligible to Receive
|  | (in thousands) |  |  |  | (in thousands)
Unvested at December 31, 2016 |  | 463 |  |  | $ | 28.02 |  |  | 844 |
Granted |  | 195 |  |  | 41.55 |  |  | 332 |
Vested |  | — |  |  | — |  |  | — |
Canceled |  | — |  |  | — |  |  | — |
Unvested at December 31, 2017 |  | 658 |  |  | $ | 32.03 |  |  | 1,176 |
Expected to vest |  | 926 |  |  |  |  |

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- Definition Tabular disclosure of the changes in outstanding nonvested shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=96867065&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=96867065&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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