Restructuring and Other Related Charges (Narrative) (Detail) - T21 $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) employee
Restructuring Cost and Reserve [Line Items]
Expected number of positions eliminated	80
Number of positions eliminated	60
Expected cost remaining \| $	$ 55

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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