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/(Loss), 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, 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	739,068					278,814
Other Comprehensive Income/(Loss), Net of Tax	(589)					(58)
Balance (in shares) at Jun. 30, 2022		346,411,029					6,035,205
Balance at Jun. 30, 2022	15,057,215	$ 1,796,056	8,242,346	5,301,054	(42,864)	5,629,278	$ 60,352	3,210,765	2,357,968	193
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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	293,742			293,742		125,838			125,838
Dividends on Preferred Stock	(1,880)			(1,880)		(1,390)			(1,390)
Dividends on Common Stock	(219,877)			(219,877)		(73,100)			(73,100)
Capital Contributions from Eversource Parent						100,000		100,000
Other Comprehensive Income/(Loss), Net of Tax	(1,293)				(1,293)	(23)				(23)
Balance (in shares) at Jun. 30, 2022		346,411,029					6,035,205
Balance at Jun. 30, 2022	$ 15,057,215	$ 1,796,056	8,242,346	5,301,054	(42,864)	5,629,278	$ 60,352	3,210,765	2,357,968	193
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/(Loss), Net of Tax	3,230				3,230	36				36
Balance (in shares) at Mar. 31, 2023		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
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	510,340					281,716
Other Comprehensive Income/(Loss), Net of Tax	$ 7,318					29
Balance (in shares) at Jun. 30, 2023	349,021,936	349,021,936					6,035,205
Balance at Jun. 30, 2023	$ 15,554,098	$ 1,799,920	8,428,786	5,562,889	(32,103)	5,898,145	$ 60,352	3,260,765	2,576,830	198
Balance (in shares) at Mar. 31, 2023		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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	17,302			17,302		133,300			133,300
Dividends on Preferred Stock	(1,880)			(1,880)		(1,390)			(1,390)
Dividends on Common Stock	(235,491)			(235,491)		(82,600)			(82,600)
Other Comprehensive Income/(Loss), Net of Tax	$ 4,088				4,088	(7)				(7)
Balance (in shares) at Jun. 30, 2023	349,021,936	349,021,936					6,035,205
Balance at Jun. 30, 2023	$ 15,554,098	$ 1,799,920	$ 8,428,786	$ 5,562,889	$ (32,103)	$ 5,898,145	$ 60,352	$ 3,260,765	$ 2,576,830	$ 198