Nuclear Decommissioning Fund (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021		Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unrealized Gain on Securities	$ 1,300		$ 981
Unrealized Loss on Securities	7		5
Investments [Abstract]
Miscellaneous investments	52		53
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	(4)
Due in 1 to 5 Years	149
Due in 5 to 10 Years	208
Due after 10 Years	314
Total	675
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Cost
Investments [Abstract]
Decommissioning Fund Investments	1,962	[1]	1,801	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Cost | Cash equivalents
Investments [Abstract]
Cash equivalents	64	[1]	40	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Cost | Commingled Funds
Investments [Abstract]
Comingled funds	856	[1]	787	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Cost | Debt Securities [Member]
Investments [Abstract]
Debt securities	631	[1]	528	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Cost | Equity Securities
Investments [Abstract]
Equity securities	411	[1]	446	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value
Investments [Abstract]
Alternative Investment	1,294	[1]	1,041	[2]
Decommissioning Fund Investments	3,256	[1]	2,777	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Cash equivalents
Investments [Abstract]
Cash equivalents	64	[1]	40	[2]
Alternative Investment	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Commingled Funds
Investments [Abstract]
Comingled funds	1,294	[1]	1,041	[2]
Alternative Investment	1,294	[1]	1,041	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Debt Securities [Member]
Investments [Abstract]
Debt securities	675	[1]	585	[2]
Alternative Investment	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Equity Securities
Investments [Abstract]
Equity securities	1,223	[1]	1,111	[2]
Alternative Investment	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 1
Investments [Abstract]
Decommissioning Fund Investments	1,286	[1]	1,149	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Cash equivalents
Investments [Abstract]
Cash equivalents	64	[1]	40	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Commingled Funds
Investments [Abstract]
Comingled funds	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Debt Securities [Member]
Investments [Abstract]
Debt securities	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Equity Securities
Investments [Abstract]
Equity securities	1,222	[1]	1,109	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 2
Investments [Abstract]
Decommissioning Fund Investments	667	[1]	574	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Cash equivalents
Investments [Abstract]
Cash equivalents	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Commingled Funds
Investments [Abstract]
Comingled funds	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Debt Securities [Member]
Investments [Abstract]
Debt securities	666	[1]	572	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Equity Securities
Investments [Abstract]
Equity securities	1	[1]	2	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 3
Investments [Abstract]
Decommissioning Fund Investments	9	[1]	13	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Cash equivalents
Investments [Abstract]
Cash equivalents	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Commingled Funds
Investments [Abstract]
Comingled funds	0	[1]	0	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Debt Securities [Member]
Investments [Abstract]
Debt securities	9	[1]	13	[2]
Nuclear Decommissioning Fund [Member] | Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Equity Securities
Investments [Abstract]
Equity securities	$ 0	[1]	$ 0	[2]

[1] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheet, which also includes $52 million of rabbi trust assets and miscellaneous investments.

[2] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheet, which also includes $53 million of rabbi trust assets and miscellaneous investments.