Employee Benefits- Fair Value of Investments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Large-cap value | Minimum
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Shares	100
Large-cap value | Maximum
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Shares	160
International value
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Percentage	8000.00%
Fixed Income Investments
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Percentage	8000.00%
Fourth Funds Targets Investments
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Percentage	6500.00%
GSE certificates
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Percentage	5000.00%
Large cap value | Minimum
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Shares	60
Large cap value | Maximum
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Shares	70
Pension Plan
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 253	$ 228	$ 283
Pension Plan | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	240
Pension Plan | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	13
Pension Plan | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Large-cap value
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	12
Pension Plan | Large-cap value | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	12
Pension Plan | Large-cap value | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Large-cap value | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Large-cap growth
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	22
Pension Plan | Large-cap growth | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	22
Pension Plan | Large-cap growth | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Large-cap growth | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Large-cap core
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	17
Pension Plan | Large-cap core | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	17
Pension Plan | Large-cap core | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Large-cap core | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Mid-cap core
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	15
Pension Plan | Mid-cap core | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	15
Pension Plan | Mid-cap core | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Mid-cap core | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Small-cap core
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	16
Pension Plan | Small-cap core | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	16
Pension Plan | Small-cap core | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Small-cap core | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | International growth
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	18
Pension Plan | International growth | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	18
Pension Plan | International growth | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | International growth | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | International value
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	10
Pension Plan | International value | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	10
Pension Plan | International value | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | International value | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Fixed Income Funds, Intermediate Core Plus
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	98
Pension Plan | Fixed Income Funds, Intermediate Core Plus | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	98
Pension Plan | Fixed Income Funds, Intermediate Core Plus | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Fixed Income Funds, Intermediate Core Plus | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Company common stock
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	31
Pension Plan | Company common stock | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	31
Pension Plan | Company common stock | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Company common stock | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Large cap value
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	13
Pension Plan | Large cap value | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Large cap value | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	13
Pension Plan | Large cap value | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Money market
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1
Pension Plan | Money market | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1
Pension Plan | Money market | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount
Pension Plan | Money market | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 0