Share-Based Compensation - Performance Thresholds (Details) - Market-Based Restricted Stock Units	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR, minimum	8.00%
TSR, target	10.00%
TSR, maximum	12.00%
Market performance percentage, minimum	50.00%
Market performance percentage, target	100.00%
Market performance percentage, maximum	150.00%

Share-based Compensation Arrangement by Share-based Payment Award, Performance Payout Percentage, Maximum

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Share-based Compensation Arrangement by Share-based Payment Award, Performance Threshold Percentage, Maximum

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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.

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