SHARE-BASED COMPENSATION - SHARE-BASED COMPENSATION EXPENSE/ OPTIONS (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Number of shares authorized for issuance (in shares)	15,400,000
Number of shares available for future grants (in shares)	6,544,164
Share-based compensation expense, before income taxes	$ 56.0	$ 77.0	$ 71.0
Income tax benefit	(6.0)	(9.0)	(9.0)
Share-based compensation expense, after tax	50.0	68.0	62.0
Capitalized share-based compensation cost	8.0	13.0	12.0
Excess income tax (benefit) deficiency	$ (15.0)	$ (9.0)	$ (6.0)
Non-qualified stock options granted (in shares)	303,614	414,812	326,574
Stock option exercise period (in years)	3 years
Weighted-average fair value for options granted (in dollars per share)	$ 20.58	$ 16.43	$ 17.50
Stock price volatility (as a percent)	26.85%	26.49%	27.35%
Expected term (in years)	5 years 4 months 9 days	5 years 4 months 9 days	5 years 4 months 9 days
Risk-free rate of return (as a percent)	4.35%	3.90%	3.89%
Annual dividend yield (as a percent)	2.85%	3.14%	2.98%
Common shares under options
Beginning balance (in shares)	2,030,666
Options granted in period (in shares)	303,614	414,812	326,574
Ending balance (in shares)	2,334,280	2,030,666
Vested at period end (in shares)	2,334,280
Exercisable at period end (in shares)	1,645,270
Weighted- average exercise price
Beginning balance (in dollars per share)	$ 68.22
Granted (in dollars per share)	87.13
Ending balance (in dollars per share)	70.68	$ 68.22
Vested at period end, Weighted- average exercise price (in dollars per share)	70.68
Exercisable at period end, Weighted- average exercise price (in dollars per share)	$ 66.37
Outstanding at period end, Weighted- average remaining contractual term	6 years 2 months 12 days
Vested at period end, Weighted- average remaining contractual term	6 years 2 months 12 days
Exercisable at period end, Weighted- average remaining contractual term	5 years 3 months 29 days
Outstanding at period end, Aggregate intrinsic value	$ 41.0
Vested at period end, Aggregate intrinsic value	41.0
Exercisable at period end, Aggregate intrinsic value	36.0
Aggregate intrinsic value of options exercised	$ 0.0	$ 4.4	$ 0.0
Weighted average period over which unrecognized compensation cost will be recognized (in years)	4 months 24 days
Weighted-average per share fair value for nonqualified stock options granted (in dollars per share)		$ 75.82	$ 76.86
SDG&E
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense, before income taxes	$ 8.0	$ 12.0	$ 13.0
Income tax benefit	(1.0)	(2.0)	(2.0)
Share-based compensation expense, after tax	7.0	10.0	11.0
Capitalized share-based compensation cost	5.0	7.0	7.0
Excess income tax (benefit) deficiency	(3.0)	(1.0)	(1.0)
SoCalGas
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense, before income taxes	10.0	20.0	18.0
Income tax benefit	(2.0)	(4.0)	(3.0)
Share-based compensation expense, after tax	8.0	16.0	15.0
Capitalized share-based compensation cost	3.0	6.0	5.0
Excess income tax (benefit) deficiency	$ (3.0)	$ (2.0)	$ (1.0)
Share-based Payment Arrangement, Option
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Award vesting period	3 years
Expiration period	10 years
Performance Shares
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Award vesting period	3 years
Award vesting rights maximum additional award	100.00%
Restricted Stock Units (RSUs), Service-based | Share-Based Payment Arrangement, Tranche One
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Award vesting period	1 year
Restricted Stock Units (RSUs), Service-based | Share-Based Payment Arrangement, Tranche Two
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Award vesting period	2 years
Restricted Stock Units (RSUs), Service-based | Share-Based Payment Arrangement, Tranche Three
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Award vesting period	3 years
Restricted Stock Units (RSUs), Service-based | Share-Based Payment Arrangement, Tranche Four
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Award vesting period	4 years
Minimum | Restricted Stock Units (RSUs), Service-based
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Award requisite service period	3 years