CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Operating Revenues	$ 1,047,481	$ 1,111,426	$ 2,282,732	$ 2,450,845
Operating Expenses:
Fuel, Purchased and Net Interchange Power	340,300	442,230	814,409	1,045,578
Other Operating Expenses	262,818	206,664	514,796	454,937
Maintenance	78,825	66,817	146,589	112,454
Depreciation	73,637	79,075	147,588	157,731
Amortization of Regulatory Assets/(Liabilities), Net	17,262	8,893	51,669	566
Amortization of Rate Reduction Bonds	17,086	54,997	34,367	114,567
Taxes Other Than Income Taxes	79,419	74,406	167,823	160,005
Total Operating Expenses	869,347	933,082	1,877,241	2,045,838
Operating Income	178,134	178,344	405,491	405,007
Interest Expense:
Interest on Long-Term Debt	57,044	58,522	114,444	115,791
Interest on Rate Reduction Bonds	2,293	5,633	4,871	12,324
Other Interest	2,897	3,042	1,468	6,343
Total Interest Expense	62,234	67,197	120,783	134,458
Other Income/(Loss), Net	7,334	1,552	17,647	9,608
Income Before Income Tax Expense	123,234	112,699	302,355	280,157
Income Tax Expense	44,515	39,351	108,052	119,209
Net Income	78,719	73,348	194,303	160,948
Net Income Attributable to Noncontrolling Interests	1,441	1,402	2,870	2,792
Net Income Attributable to Controlling Interests	77,278	71,946	191,433	158,156
Earnings Per Share Basic And Diluted	$ 0.44	$ 0.41	$ 1.08	$ 0.90
Common Stock Dividends Per Share Declared	$ 0.28	$ 0.26	$ 0.55	$ 0.51
Weighted Average Common Shares Outstanding:
Basic	177,347,374	176,571,189	177,267,791	176,460,476
Diluted	177,626,992	176,736,532	177,553,995	176,637,003
The Connecticut Light and Power Company [Member]
Operating Revenues	608,013	707,917	1,281,695	1,502,897
Operating Expenses:
Fuel, Purchased and Net Interchange Power	207,163	290,553	462,533	653,374
Other Operating Expenses	139,308	120,293	273,570	255,106
Maintenance	41,869	32,821	82,651	54,660
Depreciation	38,442	47,944	77,917	95,469
Amortization of Regulatory Assets/(Liabilities), Net	13,705	20,640	33,049	22,311
Amortization of Rate Reduction Bonds	0	38,924	0	82,207
Taxes Other Than Income Taxes	52,727	50,585	111,193	108,114
Total Operating Expenses	493,214	601,760	1,040,913	1,271,241
Operating Income	114,799	106,157	240,782	231,656
Interest Expense:
Interest on Long-Term Debt	33,430	33,630	66,758	67,262
Interest on Rate Reduction Bonds	0	2,243	0	5,275
Other Interest	868	1,334	(2,708)	3,197
Total Interest Expense	34,298	37,207	64,050	75,734
Other Income/(Loss), Net	2,058	745	6,663	5,678
Income Before Income Tax Expense	82,559	69,695	183,395	161,600
Income Tax Expense	29,924	25,610	66,423	69,102
Net Income	52,635	44,085	116,972	92,498
Public Service Company of New Hampshire [Member]
Operating Revenues	240,191	238,322	509,661	496,890
Operating Expenses:
Fuel, Purchased and Net Interchange Power	69,342	83,253	156,474	187,024
Other Operating Expenses	54,226	56,073	110,647	119,199
Maintenance	29,859	25,625	48,563	41,627
Depreciation	18,122	16,020	36,030	31,988
Amortization of Regulatory Assets/(Liabilities), Net	2,465	(11,627)	18,032	(17,322)
Amortization of Rate Reduction Bonds	13,004	12,246	26,139	24,637
Taxes Other Than Income Taxes	15,234	13,348	28,902	26,426
Total Operating Expenses	202,252	194,938	424,787	413,579
Operating Income	37,939	43,384	84,874	83,311
Interest Expense:
Interest on Long-Term Debt	8,317	9,268	16,941	18,780
Interest on Rate Reduction Bonds	1,676	2,516	3,570	5,237
Other Interest	408	185	346	364
Total Interest Expense	10,401	11,969	20,857	24,381
Other Income/(Loss), Net	4,361	(197)	8,820	2,215
Income Before Income Tax Expense	31,899	31,218	72,837	61,145
Income Tax Expense	10,234	9,602	23,708	23,719
Net Income	21,665	21,616	49,129	37,426
Western Massachusetts Electric Company [Member]
Operating Revenues	98,390	92,473	205,074	192,680
Operating Expenses:
Fuel, Purchased and Net Interchange Power	32,617	36,720	72,821	80,352
Other Operating Expenses	26,376	23,067	52,606	46,293
Maintenance	4,214	5,367	8,986	9,909
Depreciation	6,625	5,868	12,963	11,821
Amortization of Regulatory Assets/(Liabilities), Net	1,796	(721)	1,196	(2,290)
Amortization of Rate Reduction Bonds	4,082	3,827	8,228	7,722
Taxes Other Than Income Taxes	4,203	4,080	8,745	8,163
Total Operating Expenses	79,913	78,208	165,545	161,970
Operating Income	18,477	14,265	39,529	30,710
Interest Expense:
Interest on Long-Term Debt	4,722	4,726	9,476	8,607
Interest on Rate Reduction Bonds	617	874	1,301	1,811
Other Interest	121	57	257	183
Total Interest Expense	5,460	5,657	11,034	10,601
Other Income/(Loss), Net	242	161	981	765
Income Before Income Tax Expense	13,259	8,769	29,476	20,874
Income Tax Expense	5,088	3,520	11,339	9,966
Net Income	$ 8,171	$ 5,249	$ 18,137	$ 10,908