THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($) $ in Thousands	Total	Common Stock	Capital Surplus, Paid In	Retained Earnings	Accumulated Other Comprehensive Income	The Connecticut Light and Power Company	The Connecticut Light and Power Company Common Stock	The Connecticut Light and Power Company Capital Surplus, Paid In	The Connecticut Light and Power Company Retained Earnings	The Connecticut Light and Power Company Accumulated Other Comprehensive Income
Beginning balance (in shares) at Dec. 31, 2024		366,608,052					6,035,205
Beginning balance at Dec. 31, 2024	$ 15,039,387	$ 1,878,622	$ 9,428,905	$ 3,929,141	$ (26,472)	$ 6,563,882	$ 60,352	$ 3,684,265	$ 2,819,107	$ 158
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income						156,236			156,236
Dividends on Preferred Stock	(1,880)			(1,880)		(1,390)			(1,390)
Dividends on Common Stock	(276,229)			(276,229)		(247,000)			(247,000)
Other Comprehensive Income (Loss)						(6)				(6)
Ending balance (in shares) at Mar. 31, 2025		367,307,083					6,035,205
Ending balance at Mar. 31, 2025	$ 15,341,257	$ 1,878,622	9,440,596	4,203,700	(23,949)	6,471,722	$ 60,352	3,684,265	2,726,953	152
Beginning balance (in shares) at Dec. 31, 2025	375,416,880	375,416,880					6,035,205
Beginning balance at Dec. 31, 2025	$ 16,197,271	$ 1,914,273	9,937,878	4,504,983	(20,507)	6,679,626	$ 60,352	3,684,265	2,934,877	132
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income						139,329			139,329
Dividends on Preferred Stock	(1,880)			(1,880)		(1,390)			(1,390)
Dividends on Common Stock	$ (295,978)			(295,978)		(88,400)			(88,400)
Other Comprehensive Income (Loss)						(7)				(7)
Ending balance (in shares) at Mar. 31, 2026	375,974,644	375,974,644					6,035,205
Ending balance at Mar. 31, 2026	$ 16,530,950	$ 1,914,273	$ 9,950,113	$ 4,815,846	$ (20,377)	$ 6,729,158	$ 60,352	$ 3,684,265	$ 2,984,416	$ 125