Derivative Instruments and Hedging Activities - Commodity Purchases (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Commodity Purchases [Line Items]
Derivative Net Liability Position Containing Credit Risk Related Contingency Feature	$ 0
Aggregate fair value of additional collateral requirements in the event of a credit downgrade below investment grade	0
Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Liability value	11	$ 16
Asset value	22	9
Other Current Assets | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Asset value	16	7
Other Current Assets | Gas Contract | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Asset value	16	7
Other Current Assets | Interest Rate Swaps [Member] | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Asset value	0	0
Other Current Liabilities | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Liability value	2	10
Other Current Liabilities | Gas Contract | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Liability value	1	10
Other Current Liabilities | Interest Rate Swaps [Member] | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Liability value	1	0
Other Noncurrent Assets [Member] | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Asset value	6	2
Other Noncurrent Assets [Member] | Gas Contract | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Asset value	6	2
Other Noncurrent Assets [Member] | Interest Rate Swaps [Member] | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Asset value	0	0
Other Noncurrent Liabilities | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Liability value	9	6
Other Noncurrent Liabilities | Gas Contract | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Liability value	$ 5	3
Other Noncurrent Liabilities | Interest Rate Swaps [Member] | Not Designated As Hedging Instruments [Member]
Commodity Purchases [Line Items]
Liability value		$ 3