SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES STOCK-BASED COMPENSATION (Details) - $ / shares	1 Months Ended	3 Months Ended	12 Months Ended
	Jan. 31, 2023	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of WEC Energy Group common stock authorized for issuance			9,000,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)			3 years
Minimum exercise price of stock option as a percent of WEC Energy Group common stock fair value on the grant date			100.00%
Period after the grant date during which stock options can't be exercised (in months)			6 months
Maximum term of awards			10 years
Stock options granted			16,079	18,021	22,042
Estimated weighted-average fair value per stock option (in dollars per share)			$ 14.71	$ 13.20	$ 10.82
Risk-free interest rate, minimum (as a percent)			0.20%	0.10%	1.60%
Risk-free interest rate, maximum (as a percent)			1.60%	0.90%	1.90%
Dividend yield (as a percent)			3.20%	2.90%	3.00%
Expected Volatility (as a percent)			21.00%	21.00%	16.00%
Expected life (years)			8 years 8 months 12 days	8 years 8 months 12 days	8 years 7 months 6 days
Stock options | Subsequent event
Share-based Compensation Arrangement by Share-based Payment Award
Stock options granted		10,655
Estimated weighted-average fair value per stock option (in dollars per share)		$ 19.58
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)			3 years
Percentage to vest each year after the grant date			33.00%
Performance units
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)			3 years
Performance units | Performance units granted prior to 2023
Share-based Compensation Arrangement by Share-based Payment Award
Maximum adjustment to payout ratio			10.00%
Performance units | Performance units granted prior to 2023 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Payout ratio (as a percent)			0.00%
Performance units | Performance units granted prior to 2023 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Payout ratio (as a percent)			175.00%
Performance units | Performance units granted in 2023 | Subsequent event
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)	3 years
Maximum adjustment to payout ratio	25.00%
Percentage of payout based on total shareholder return	55.00%
Percentage of payout based on ROE	45.00%
Performance units | Performance units granted in 2023 | Maximum | Subsequent event
Share-based Compensation Arrangement by Share-based Payment Award
Payout ratio (as a percent)	200.00%