Incentive Plans (Summary For Future Stock-Based Compensation Expense) (Detail) $ in Millions	Mar. 31, 2017 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining 2017	$ 44
2018	34
2019	15
Thereafter	2
Total	$ 95

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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