v3.20.4
Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Costs - Footnotes (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]      
Restructuring charge [1] $ 556 $ 227 [2] $ 796
Acquisition-related Costs [Member]      
Restructuring Cost and Reserve [Line Items]      
Restructuring charge   (192) 37
Cost Reduction Initiatives [Member]      
Restructuring Cost and Reserve [Line Items]      
Restructuring charge $ 556 418 $ 759
Restructuring Charges And Acquisition-Related Costs [Member] | Array [Member]      
Restructuring Cost and Reserve [Line Items]      
Post closing compensation expense   $ 157  
[1] Represents acquisition-related costs ($192 million credit in 2019, and $37 million charge in 2018) and cost reduction initiatives ($556 million charge in 2020, $418 million charge in 2019, and $759 million charge in 2018). 2020 charges mainly represent employee termination costs for our Transforming to a More Focused Company cost-reduction program. 2019 restructuring charges mainly represent employee termination costs for cost-reduction and productivity initiatives, partially offset by the reversal of certain accruals related to our acquisition of Wyeth upon the effective favorable settlement of an IRS audit for multiple tax years (see Note 5B). 2018 charges were primarily related to employee termination costs and asset write downs. The employee termination costs for 2019 and 2018 were primarily for our improvements to operational effectiveness as part of the realignment of our business structure, and for 2019, also includes employee termination costs for the Transforming to a More Focused Company cost-reduction program.
[2] Includes the reversal of certain accruals related to our acquisition of Wyeth upon the favorable settlement of an IRS audit for multiple tax years. See Note 5D.