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v3.21.2

Pension and Other Postretirement Benefits - Additional Information (Detail) $ in Millions |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Apr. 01, 2021 USD ($) | Jun. 30, 2021 USD ($) | Mar. 31, 2021 USD ($) Employee | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Company's contribution | $ 500 |  |  |  |
Minimum required cash contribution to pension plans reminder of 2021 |  | $ 80 |  | $ 80 |
United States [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Minimum required cash contribution to pension plans |  | 54 |  | 49 | $ 40
Non-U.S. [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Minimum required cash contribution to pension plans |  | 6 |  | 20 | $ 19
Warrick Rolling Mill [Member] | Held for Sale [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Sale transaction value of waste processing |  |  | $ 670 |  |
Assumption of other postretirement benefit liabilities |  | 66 |  | 66 |
Decrease in other postretirement benefit liabilities after post closing adjustment |  | 6 |  |  |
Number of employees | Employee |  |  | 1,150 |  |
Action# 1 [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Decrease to accrued other postretirement benefits liability |  |  |  | 106 |
Curtailment gain |  |  |  | 17 |
Settlement charge |  |  |  | 26 |
Action# 1 [Member] | Warrick Rolling Mill [Member] | Held for Sale [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Sale transaction value of waste processing |  |  | $ 670 |  |
Assumption of other postretirement benefit liabilities |  | 66 |  | 66 |
Decrease in other postretirement benefit liabilities after post closing adjustment |  | 6 |  |  |
Number of employees | Employee |  |  | 1,150 |  |
Decrease to accrued other postretirement benefits liability |  |  | $ 40 |  |
Remeasurement to accrued other postretirement benefits liability |  |  |  | 66 |
Curtailment gain |  |  | 17 |  |
Settlement charge |  |  | $ 26 |  |
Action# 2 [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Settlement charge |  |  |  | 39 |
Decrease to accrued other pension benefits liability |  |  |  | $ 90 |
Action# 2 [Member] | Warrick Rolling Mill [Member] | Held for Sale [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Settlement charge |  | 39 |  |  |
Decrease to accrued other pension benefits liability |  | $ 90 |  |  |

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