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		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	$ 718	$ (772)	$ (2,519)	$ (941)
Total loss on settled derivatives	(1,601)	(99)	(2,296)	(121)
Non-performance risk adjustment	4	0	9	0
Total loss on derivatives	(879)	(871)	(4,806)	(1,062)
Fixed price swaps | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	339	(221)	(1,514)	(243)
Total loss on settled derivatives	(870)	(6)	(1,167)	(1)
Fixed price swaps | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	19	(41)	(34)	(81)
Total loss on settled derivatives	(41)	(28)	(74)	(45)
Fixed price swaps | Ethane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(6)	(11)	(27)	(13)
Total loss on settled derivatives	(19)	(6)	(27)	(10)
Fixed price swaps | Propane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	56	(43)	7	(88)
Total loss on settled derivatives	(34)	(30)	(75)	(60)
Fixed price swaps | Normal Butane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	20	(19)	0	(34)
Total loss on settled derivatives	(12)	(9)	(26)	(16)
Fixed price swaps | Natural Gasoline
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	29	(11)	1	(31)
Total loss on settled derivatives	(17)	(13)	(36)	(22)
Two-way costless collars | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	9	(148)	(333)	(160)
Total loss on settled derivatives	(130)	(2)	(234)	0
Two-way costless collars | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	0	0	(1)
Total loss on settled derivatives	0	(1)	0	(2)
Two-way costless collars | Ethane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	(1)	1	(1)
Total loss on settled derivatives	0	0	(1)	0
Three-way costless collars | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	230	(249)	(494)	(249)
Total loss on settled derivatives	(396)	(8)	(517)	(7)
Three-way costless collars | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	5	(29)	(28)	(47)
Total loss on settled derivatives	(18)	(5)	(31)	(6)
Three-way costless collars | Propane
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	3	(1)	1	(2)
Total loss on settled derivatives	(1)	0	(3)	0
Basis swaps | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(28)	44	8	47
Total loss on settled derivatives	23	8	24	49
Call options | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	43	(40)	(106)	(37)
Total loss on settled derivatives	(87)	0	(126)	0
Call options | Oil
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	0	0	(1)
Put options | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	1	0	1
Total loss on settled derivatives	0	0	0	(2)
Amortization of premium paid				2
Swaptions | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	(4)	0	(3)
Purchased fixed price swaps | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	2	0	2
Total loss on settled derivatives	1	1	1	1
Purchased fixed price swaps | Natural Gas Storage
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	(1)	1	0	1
Fixed price swaps – storage | Natural Gas Storage
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	(2)	1	(2)
Total loss on settled derivatives	0	0	(3)	0
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) on unsettled derivatives	0	0	(2)	1
Index swap | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
Total loss on settled derivatives	$ 0	$ 0	$ (1)	$ 0