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Stock-Based Compensation Plans - Balance Sheet Classification of Obligations related to Outstanding Performance Share Awards Not Yet Settled (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Classification Of Obligations Related To Outstanding Performance Share Awards Not Yet Settled Current Liabilities | [1] | $ 135 | $ 57
Classification Of Obligations Related To Outstanding Performance Share Awards Not Yet Settled Deferred Credits And Other Liabilities | [2] | 109 | 100
Classification Of Obligations Related To Outstanding Performance Share Awards Not Yet Settled Common Stock |  | 26 | 26
Total Balance Sheet Classification Of Obligations Related To Outstanding Performance Share Awards Not Yet Settled |  | $ 270 | $ 183
[1] | Represents the current liability related to performance share awards expected to be settled in cash.
[2] | Represents the long-term liability related to performance share awards expected to be settled in cash.

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- Definition Classification Of Obligations Related To Outstanding Performance Share Awards Not Yet Settled Common Stock + References No definition available. + Details
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- Definition Classification Of Obligations Related To Outstanding Performance Share Awards Not Yet Settled Current Liabilities + References No definition available. + Details
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- Definition Classification Of Obligations Related To Outstanding Performance Share Awards Not Yet Settled Deferred Credits And Other Liabilities + References No definition available. + Details
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- Definition Total Balance Sheet Classification Of Obligations Related To Outstanding Performance Share Awards Not Yet Settled + 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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