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 Loss	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 Loss
Balance (in shares) at Dec. 31, 2021		344,403,196					6,035,205
Balance at Dec. 31, 2021	$ 14,599,844	$ 1,789,092	$ 8,098,514	$ 5,005,391	$ (42,275)	$ 5,299,501	$ 60,352	$ 3,010,765	$ 2,228,133	$ 251
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	445,326			445,326		152,977			152,977
Dividends on Preferred Stock	(1,880)			(1,880)		(1,390)			(1,390)
Dividends on Common Stock	(219,768)			(219,768)		(73,100)			(73,100)
Capital Contributions from Eversource Parent						100,000		100,000
Other Comprehensive Income, Net of Tax	704				704	(35)				(35)
Balance (in shares) at Mar. 31, 2022		344,850,272					6,035,205
Balance at Mar. 31, 2022	$ 14,836,690	$ 1,789,092	8,102,618	5,229,069	(41,571)	5,477,953	$ 60,352	3,110,765	2,306,620	216
Balance (in shares) at Dec. 31, 2022	348,443,855	348,443,855					6,035,205
Balance at Dec. 31, 2022	$ 15,473,158	$ 1,799,920	8,401,731	5,527,153	(39,421)	5,784,380	$ 60,352	3,260,765	2,463,094	169
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	493,039			493,039		148,416			148,416
Dividends on Preferred Stock	(1,880)			(1,880)		(1,390)			(1,390)
Dividends on Common Stock	(235,354)			(235,354)		(82,600)			(82,600)
Other Comprehensive Income, Net of Tax	$ 3,230				3,230	36				36
Balance (in shares) at Mar. 31, 2023	348,808,082	348,808,082					6,035,205
Balance at Mar. 31, 2023	$ 15,749,371	$ 1,799,920	$ 8,412,085	$ 5,782,958	$ (36,191)	$ 5,848,842	$ 60,352	$ 3,260,765	$ 2,527,520	$ 205