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Employee Benefit Plans - Defined Benefit Plan, Information about Plan Assets (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | $ 3,573 | $ 3,524
Defined Benefit Plan, Fair Value of Plan Assets, Excluded Investment Payables | 49 | 46
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 3,573 | 3,524
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 3,396 | 3,573
Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 198 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 198 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 186 | 198
Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2,313 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2,313 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 2,209 | 2,313
Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 190 | 198
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 190 | 198
Realized gains, net | 0 | (3)
Changes in unrealized gains (losses), net | 0 | 9
Purchases | 5 | 13
Sales | (21) | (30)
Transfers into Level 3 [2] | 0 | 5
Transfers out of Level 3 [2] | 0 | (2)
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 174 | 190
Pension Plan [Member] | Fair Value, Inputs, Level 1, 2 and 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 3,527 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 3,527 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 3,347 | 3,527
Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 18 | 30
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 18 | 30
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 8 | 18
Other Postretirement Benefits Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 16 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 16 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 8 | 16
Other Postretirement Benefits Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 2
Other Postretirement Benefits Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | $ 0 | $ 0
Equity Securities [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 19.00% |
Fixed income securities | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 81.00% |
Fixed income securities | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 100.00% | 100.00%
Short-term Investments [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | $ 187 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 187 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 164 | $ 187
Short-term Investments [Member] | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 187 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 187 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 164 | 187
Short-term Investments [Member] | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Short-term Investments [Member] | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Short-term Investments [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 16 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 16 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 8 | 16
Short-term Investments [Member] | Other Postretirement Benefits Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 16 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 16 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 8 | 16
Short-term Investments [Member] | Other Postretirement Benefits Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Short-term Investments [Member] | Other Postretirement Benefits Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Corporate | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 1,679 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 1,679 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 1,619 | 1,679
Corporate | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Corporate | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 1,643 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 1,643 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 1,586 | 1,643
Corporate | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 36 | 31
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 36 | 31
Realized gains, net | 0 | 0
Changes in unrealized gains (losses), net | 0 | 2
Purchases | 5 | 0
Sales | (8) | 0
Transfers into Level 3 [2] | 0 | 5
Transfers out of Level 3 [2] | 0 | (2)
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 33 | 36
Residential mortgage-backed securities ("RMBS") | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 111 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 111 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 105 | 111
Residential mortgage-backed securities ("RMBS") | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Residential mortgage-backed securities ("RMBS") | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 111 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 111 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 105 | 111
Residential mortgage-backed securities ("RMBS") | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
U.S. Treasuries | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 271 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 271 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 286 | 271
U.S. Treasuries | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 8 | 0
U.S. Treasuries | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 271 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 271 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 278 | 271
U.S. Treasuries | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
U.S. Treasuries | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 2
U.S. Treasuries | Other Postretirement Benefits Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
U.S. Treasuries | Other Postretirement Benefits Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 2
U.S. Treasuries | Other Postretirement Benefits Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Foreign government/government agencies | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 21 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 21 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 18 | 21
Foreign government/government agencies | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Foreign government/government agencies | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 11 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 11 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 9 | 11
Foreign government/government agencies | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 10 | 1
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 10 | 1
Realized gains, net | 0 | 0
Changes in unrealized gains (losses), net | (1) | (1)
Purchases | 0 | 10
Sales | 0 | 0
Transfers into Level 3 [2] | 0 | 0
Transfers out of Level 3 [2] | 0 | 0
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 9 | 10
CMBS | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 50 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 50 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 29 | 50
CMBS | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
CMBS | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 49 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 49 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 28 | 49
CMBS | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 1 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 1 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 1 | 1
Other Fixed Income [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 160 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 160 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 162 | 160
Other Fixed Income [Member] | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Other Fixed Income [Member] | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 160 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 160 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 162 | 160
Other Fixed Income [Member] | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Mortgage loans | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 143 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 143 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 131 | 143
Mortgage loans | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Mortgage loans | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Mortgage loans | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 143 | 165
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 143 | 165
Realized gains, net | 0 | (3)
Changes in unrealized gains (losses), net | 1 | 8
Purchases | 0 | 3
Sales | (13) | (30)
Transfers into Level 3 [2] | 0 | 0
Transfers out of Level 3 [2] | 0 | 0
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 131 | 143
Domestic | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 34 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 34 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 18 | 34
Domestic | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 11 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 11 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 14 | 11
Domestic | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 23 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 23 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 4 | 23
Domestic | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
International | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 45 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 45 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 37 | 45
International | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
International | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 45 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 45 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 37 | 45
International | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 0 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 0 | 0
Total pension plan assets at fair value, in the fair value hierarchy | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2,701 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2,701 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 2,569 | 2,701
Total pension plan assets at fair value, in the fair value hierarchy | Pension Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 198 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 198 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 186 | 198
Total pension plan assets at fair value, in the fair value hierarchy | Pension Plan [Member] | Significant Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2,313 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 2,313 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 2,209 | 2,313
Total pension plan assets at fair value, in the fair value hierarchy | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 190 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 190 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 174 | 190
Limited partnerships | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 826 |
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 826 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | 778 | 826
Other investments | Pension Plan [Member] | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 1 | 1
Pension Plan Asset Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Plan Assets, Amount, Beginning Balance | 1 | 1
Realized gains, net | 0 | 0
Changes in unrealized gains (losses), net | 0 | 0
Purchases | 0 | 0
Sales | 0 | 0
Transfers into Level 3 [2] | 0 | 0
Transfers out of Level 3 [2] | 0 | 0
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | $ 1 | $ 1
Minimum | Equity Securities [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 0.00% |
Minimum | Equity Securities [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 0.00% |
Minimum | Fixed income securities | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 75.00% |
Minimum | Fixed income securities | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 100.00% |
Minimum | Limited partnerships | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 0.00% |
Minimum | Limited partnerships | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 0.00% |
Maximum | Equity Securities [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 20.00% |
Maximum | Equity Securities [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 0.00% |
Maximum | Fixed income securities | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 95.00% |
Maximum | Fixed income securities | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 100.00% |
Maximum | Limited partnerships | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 25.00% |
Maximum | Limited partnerships | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocation | 0.00% |

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