v3.22.4

Accumulated Other Comprehensive (Loss) Income​​ (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
AOCI Attributable to Parent [Abstract] |  |  |
Balance at beginning of period | $ 1,559 | $ 1,447 | $ 2,973
Other comprehensive income: |  |  |
Total Other comprehensive income, net of tax | 174 | 650 | 146
Balance at end of period | 1,357 | 1,559 | 1,447
Amount related to settlement of certain employee retirement benefits | 47 | 584 | 199
Accumulated other comprehensive loss |  |  |
AOCI Attributable to Parent [Abstract] |  |  |
Balance at beginning of period | (1,111) | (1,761) | 295
Other comprehensive income: |  |  |
Total Other comprehensive income, net of tax | 174 | 650 | 146
Balance at end of period | (937) | (1,111) | (1,761)
Pension and other postretirement benefits |  |  |
AOCI Attributable to Parent [Abstract] |  |  |
Balance at beginning of period | (1,121) | (1,791) | (43)
Establishment of additional defined benefit plans | 0 | 0 | (1,752)
Separation-related adjustments | 0 | 0 | (50)
Other comprehensive income: |  |  |
Unrecognized net actuarial loss and prior service benefit / Net change from periodic revaluations | 176 | 190 | (259)
Tax (expense) benefit | (41) | (43) | 62
Total Other comprehensive income (loss) before reclassifications, net of tax | 135 | 147 | (197)
Amortization of net actuarial loss and prior service benefit / Net amount reclassified to earnings | 124 | 680 | 326
Tax expense | (30) | (157) | (75)
Total amount reclassified from Accumulated other comprehensive loss, net of tax | 94 | 523 | 251
Total Other comprehensive income, net of tax | 229 | 670 | 54
Balance at end of period | (892) | (1,121) | (1,791)
Foreign currency translation |  |  |
AOCI Attributable to Parent [Abstract] |  |  |
Balance at beginning of period | 25 | 29 | 338
Separation-related adjustments | 0 | 0 | (396)
Other comprehensive income: |  |  |
Total Other comprehensive income (loss) before reclassifications, net of tax | (76) | (4) | 65
Total amount reclassified from Accumulated other comprehensive loss, net of tax | 0 | 0 | 22
Total Other comprehensive income, net of tax | (76) | (4) | 87
Balance at end of period | (51) | 25 | 29
Cash flow hedges |  |  |
AOCI Attributable to Parent [Abstract] |  |  |
Balance at beginning of period | (15) | 1 | 0
Separation-related adjustments | 0 | 0 | (4)
Other comprehensive income: |  |  |
Unrecognized net actuarial loss and prior service benefit / Net change from periodic revaluations | 95 | (161) | (2)
Tax (expense) benefit | (22) | 37 | 1
Total Other comprehensive income (loss) before reclassifications, net of tax | 73 | (124) | (1)
Amortization of net actuarial loss and prior service benefit / Net amount reclassified to earnings | (67) | 140 | 8
Tax expense | 15 | (32) | (2)
Total amount reclassified from Accumulated other comprehensive loss, net of tax | (52) | 108 | 6
Total Other comprehensive income, net of tax | 21 | (16) | 5
Balance at end of period | 6 | (15) | 1
Cash flow hedges | Aluminum Contract |  |  |
Other comprehensive income: |  |  |
Amortization of net actuarial loss and prior service benefit / Net amount reclassified to earnings | 48 | (142) | (8)
Cash flow hedges | Energy Related Derivative |  |  |
Other comprehensive income: |  |  |
Amortization of net actuarial loss and prior service benefit / Net amount reclassified to earnings | 20 | 0 | 0
Cash flow hedges | Commodity Contract |  |  |
Other comprehensive income: |  |  |
Amortization of net actuarial loss and prior service benefit / Net amount reclassified to earnings | $ (1) | $ 2 | $ 0

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