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Schedule I - Condensed Financial Information of Parent (Exelon Corporate) - Debt and Credit Agreements - Schedule of Outstanding Long-term Debt (Details) - USD ($) $ in Millions	Jan. 24, 2022	Jan. 21, 2022	Dec. 31, 2022	Jan. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt, gross			$ 36,779		$ 32,523
Unamortized debt discount and premium, net			74		70
Unamortized debt issuance costs			(257)		(220)
Long-term debt (including amounts due within one year)			626		669
Long-term Debt, Current Maturities			(1,802)		(2,153)
Long-term debt			35,272		30,749
Exelon Corporate [Member] \| Exelon Generation Co L L C [Member]
Debt Instrument [Line Items]
Due from Affiliate, Noncurrent			0	$ 258	319
Junior subordinated notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross			0		1,150
Senior unsecured notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross			8,324		6,324
Loan agreement [Member]
Debt Instrument [Line Items]
Long-term debt, gross			$ 1,400		50
Minimum [Member] \| Senior unsecured notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			2.75%
Long-term Debt, Maturity Date			Dec. 31, 2025
Minimum [Member] \| Loan agreement [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			2.00%
Long-term Debt, Maturity Date			Dec. 31, 2023
Maximum [Member] \| Junior subordinated notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			3.50%
Long-term Debt, Maturity Date			Dec. 31, 2022
Maximum [Member] \| Senior unsecured notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			7.60%
Long-term Debt, Maturity Date			Dec. 31, 2052
Maximum [Member] \| Loan agreement [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			5.15%
Long-term Debt, Maturity Date			Dec. 31, 2024
Corporate, Non-Segment [Member]
Debt Instrument [Line Items]
Long-term debt, gross			$ 9,489		7,289
Unamortized debt discount and premium, net			(10)		(10)
Unamortized debt issuance costs			(51)		(39)
Long-term debt (including amounts due within one year)			164		175
Long-term Debt, Current Maturities			(850)		(1,150)
Long-term debt			8,742		6,265
Due from Affiliate, Noncurrent			0		319
Corporate, Non-Segment [Member] \| Junior subordinated notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross			0		1,150
Corporate, Non-Segment [Member] \| Senior unsecured notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross			8,139		6,139
Corporate, Non-Segment [Member] \| Loan agreement [Member]
Debt Instrument [Line Items]
Long-term debt, gross		$ 300	$ 1,350		$ 0
Corporate, Non-Segment [Member] \| Loan agreement [Member] \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Subordinated Borrowing, Interest Rate		0.65%
Corporate, Non-Segment [Member] \| Loans Payable Two \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Subordinated Borrowing, Interest Rate		0.65%
Corporate, Non-Segment [Member] \| Loans Payable Three
Debt Instrument [Line Items]
Long-term debt, gross	$ 250
Corporate, Non-Segment [Member] \| Loans Payable Three \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Subordinated Borrowing, Interest Rate	0.65%
Corporate, Non-Segment [Member] \| Minimum [Member] \| Senior unsecured notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			2.75%
Long-term Debt, Maturity Date			Dec. 31, 2025
Corporate, Non-Segment [Member] \| Minimum [Member] \| Loan agreement [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			4.95%
Long-term Debt, Maturity Date			Dec. 31, 2023
Corporate, Non-Segment [Member] \| Maximum [Member] \| Junior subordinated notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			3.50%
Long-term Debt, Maturity Date			Dec. 31, 2022
Corporate, Non-Segment [Member] \| Maximum [Member] \| Senior unsecured notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			7.60%
Long-term Debt, Maturity Date			Dec. 31, 2052
Corporate, Non-Segment [Member] \| Maximum [Member] \| Loan agreement [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			5.15%
Long-term Debt, Maturity Date			Dec. 31, 2024