Derivatives and Risk Management (Summary of Before Tax Effect of Fair Value Hedges not Designated for Hedge Accounting) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	$ (69)	$ (12)	$ 1,566	$ (2,531)
Total gain (loss) on settled derivatives	162	(1,889)	249	(4,185)
Non-performance risk adjustment	0	(2)	(4)	7
Total gain (loss) on derivatives	93	(1,903)	1,811	(6,709)
Fixed price swaps | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	28	(140)	965	(1,654)
Total gain (loss) on settled derivatives	112	(1,082)	227	(2,249)
Fixed price swaps | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(29)	73	(7)	39
Total gain (loss) on settled derivatives	(11)	(30)	(18)	(104)
Fixed price swaps | Ethane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(5)	24	(5)	(3)
Total gain (loss) on settled derivatives	(3)	(15)	3	(42)
Fixed price swaps | Propane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(37)	67	(8)	74
Total gain (loss) on settled derivatives	9	(21)	21	(96)
Fixed price swaps | Normal Butane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(6)	24	1	24
Total gain (loss) on settled derivatives	1	(7)	2	(33)
Fixed price swaps | Natural Gasoline
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(9)	28	(2)	29
Total gain (loss) on settled derivatives	0	(9)	1	(45)
Two-way costless collars | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	3	(99)	233	(432)
Total gain (loss) on settled derivatives	13	(152)	44	(386)
Two-way costless collars | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(4)	0	(3)	0
Two-way costless collars | Ethane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	0	0	1
Total gain (loss) on settled derivatives	0	0	0	(1)
Three-way costless collars | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	20	(26)	310	(520)
Total gain (loss) on settled derivatives	1	(491)	(15)	(1,008)
Three-way costless collars | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(1)	38	20	10
Total gain (loss) on settled derivatives	(7)	(12)	(20)	(43)
Three-way costless collars | Propane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	3	0	4
Total gain (loss) on settled derivatives	0	(1)	0	(4)
Basis swaps | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(43)	4	25	12
Total gain (loss) on settled derivatives	47	40	11	64
Index swap | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on settled derivatives	0	0	0	(1)
Call options | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	14	(8)	41	(114)
Total gain (loss) on settled derivatives	0	(109)	(7)	(235)
Put options | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	0	(4)	0
Purchased fixed price swaps | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on settled derivatives	0	0	0	1
Fixed price swaps – storage | Natural Gas Storage
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	0	0	1
Total gain (loss) on settled derivatives	0	0	0	(3)
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	$ 0	$ 0	$ 0	$ (2)