Balance Sheets - MEC (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Common stock, shares authorized (in shares)	115,000,000	115,000,000
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares issued (in shares)	76,000,000	76,000,000
Common stock, shares outstanding (in shares)	76,000,000	76,000,000
MEC
Common stock, shares authorized (in shares)	350,000,000	350,000,000
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares issued (in shares)	71,000,000	71,000,000
Common stock, shares outstanding (in shares)	71,000,000	71,000,000