CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
COMPREHENSIVE INCOME:
Net income and comprehensive income	$ 3,388.6	$ 2,434.7	$ 2,648.0
Other comprehensive income (loss) net of tax:
-Decrease (increase) in pension and other post-retirement benefits (net of income tax of $(3.8), $(0.4) and $(0.2), respectively)	5.8	1.0	1.0
-Derivative instruments classified as cash flow hedge
- Unrealized (loss) on derivative instruments classified as cash flow hedge (net of income tax of $0.2 million in 2022)			(0.6)
Total other comprehensive income (loss)	5.8	1.0	0.4
Total comprehensive income	3,394.4	2,435.7	2,648.4
Comprehensive income attributable to the non-controlling interest	11.8	9.5	9.5
Comprehensive income attributable to SCC	$ 3,382.6	$ 2,426.2	$ 2,638.9