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
	Mar. 31, 2023	Mar. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	$ 1,528	$ (3,237)
Total loss on settled derivatives	(123)	(695)
Non-performance risk adjustment	(4)	5
Total gain (loss) on derivatives	1,401	(3,927)
Fixed price swaps | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	961	(1,853)
Total loss on settled derivatives	(45)	(297)
Fixed price swaps | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	12	(53)
Total loss on settled derivatives	(4)	(33)
Fixed price swaps | Ethane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	9	(21)
Total loss on settled derivatives	1	(8)
Fixed price swaps | Propane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	1	(49)
Total loss on settled derivatives	1	(41)
Fixed price swaps | Normal Butane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	1	(20)
Total loss on settled derivatives	0	(14)
Fixed price swaps | Natural Gasoline
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	1	(28)
Total loss on settled derivatives	0	(19)
Two-way costless collars | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	241	(342)
Total loss on settled derivatives	0	(104)
Two-way costless collars | Ethane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	1
Total loss on settled derivatives	0	(1)
Three-way costless collars | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	263	(724)
Total loss on settled derivatives	(33)	(121)
Three-way costless collars | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	12	(33)
Total loss on settled derivatives	(7)	(13)
Three-way costless collars | Propane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	(2)
Total loss on settled derivatives	0	(2)
Basis swaps | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(30)	36
Total loss on settled derivatives	(29)	1
Index swap | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total loss on settled derivatives	0	(1)
Call options | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	61	(149)
Total loss on settled derivatives	(7)	(39)
Put options | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(4)	0
Purchased fixed price swaps | Natural Gas Storage
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	1
Fixed price swaps – storage | Natural Gas Storage
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	1
Total loss on settled derivatives	0	(3)
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	$ 0	$ (2)