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Share-Based Compensation Plans - Performance Share Awards Narrative (Details) - Performance Shares | 6 Months Ended
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Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Vesting conditions period (in years) | 3 years
Minimum |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Shares issued, percent | 0.00%
Maximum |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Shares issued, percent | 200.00%

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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued, Percent + References No definition available. + Details
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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Vesting Conditions Period + References No definition available. + 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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- Details
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- Details
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Period Type: |

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- Details
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