Restructuring (Narrative) (Detail) - T19 Restructuring [Member] $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($) Employee
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Number of Positions Eliminated	240
Restructuring and Related Cost, Number of Positions Eliminated	225
Restructuring and Related Cost, Expected Cost Remaining \| $	$ 25

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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