Contribution Plan (Details 7) - USD ($) $ in Millions |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Other Pension Plan | |||
| Defined Contribution Plan Disclosure [Line Items] | |||
| Defined Contribution Plan, Cost | $ 84 | $ 68 | $ 74 |
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- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. No definition available.
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- Details
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