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Incentive Plans (Tables) | 12 Months Ended
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Dec. 31, 2016
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 2016:
|  | Shares |  | Weighted Average Exercise Price Per Share |  | Weighted Average Remaining Contractual Life |  | Aggregate Intrinsic Value
|  | (in thousands) |  |  |  | (in years) |  | (in thousands)
Outstanding - December 31, 2015 |  | 28 |  |  | $ | 29.56 |  |  |  |  |
Granted |  | — |  |  | — |  |  |  |  |
Exercised |  | (20 | ) |  | 29.17 |  |  |  |  |
Canceled |  | — |  |  | — |  |  |  |  |
Outstanding - December 31, 2016 |  | 8 |  |  | $ | 30.59 |  |  | 4.5 |  | $ | 315 |
Exercisable - December 31, 2016 |  | 8 |  |  | $ | 30.59 |  |  | 4.5 |  | $ | 315 |
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 2016:
|  | Shares |  | Weighted Average Grant Date Fair Value
|  | (in thousands) |  |
Non-vested - December 31, 2015 |  | 618 |  |  | $ | 37.98 |
Granted |  | 236 |  |  | 52.66 |
Vested |  | (333 | ) |  | 35.66 |
Canceled/Forfeited |  | (18 | ) |  | 44.66 |
Non-vested - December 31, 2016 |  | 503 |  |  | $ | 46.17 |
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 2016:
|  | Number of Performance Units at Target |  | Weighted Average Grant Date Fair Value |  | Maximum Shares Eligible to Receive
Unvested at December 31, 2015 |  | 100,900 |  |  | $ | 52.80 |  |  | 201,800 |
Granted |  | 133,380 |  |  | 58.42 |  |  | 224,861 |
Vested |  | — |  |  | — |  |  | — |
Canceled |  | (2,550 | ) |  | 52.80 |  |  | (4,636 | )
Unvested at December 31, 2016 |  | 231,730 |  |  | $ | 56.04 |  |  | 422,025 |
Expected to vest |  | 302,059 |  |  |  |  |

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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=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + 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)(1) -URI http://asc.fasb.org/extlink&oid=6415400&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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