Consolidated Balance Sheets - Exelon (Parentheticals) - USD ($) shares in Millions, $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Accumulated depreciation and amortization	$ 17,711	$ 17,251
Common stock (in dollars)	$ 0	$ 0
Common stock, shares authorized (in shares)	2,000	2,000
Common stock, shares outstanding (in shares)	1,000	999
Treasury stock, common (in shares)	2	2