CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Operating Revenues	$ 1,114,892	$ 1,243,337	$ 3,397,624	$ 3,694,182
Operating Expenses:
Fuel, Purchased and Net Interchange Power	399,941	494,125	1,214,350	1,539,703
Other Operating Expenses	237,576	233,472	752,372	688,409
Maintenance	58,949	49,951	205,538	162,405
Depreciation	75,196	70,954	222,784	228,685
Amortization of Regulatory Assets/(Liabilities), Net	36,740	50,341	88,409	50,908
Amortization of Rate Reduction Bonds	17,680	60,434	52,047	175,000
Taxes Other Than Income Taxes	84,994	84,427	252,817	244,431
Total Operating Expenses	911,076	1,043,704	2,788,317	3,089,541
Operating Income	203,816	199,633	609,307	604,641
Interest Expense:
Interest on Long-Term Debt	57,461	57,802	171,905	173,594
Interest on Rate Reduction Bonds	2,018	4,661	6,889	16,985
Other Interest	4,453	3,435	5,922	9,778
Total Interest Expense	63,932	65,898	184,716	200,357
Other Income/(Loss), Net	1,430	10,118	19,077	19,726
Income Before Income Tax Expense	141,314	143,853	443,668	424,010
Income Tax Expense	49,883	41,918	157,934	161,126
Net Income	91,431	101,935	285,734	262,884
Net Income Attributable to Noncontrolling Interests	1,470	1,411	4,340	4,204
Net Income Attributable to Controlling Interests	89,961	100,524	281,394	258,680
Diluted Earnings Per Common Share	$ 0.51	$ 0.57	$ 1.58	$ 1.46
Basic Earnings Per Common Share	$ 0.51	$ 0.57	$ 1.59	$ 1.47
Common Stock Dividends Per Share Declared	$ 0.28	$ 0.26	$ 0.83	$ 0.77
Weighted Average Common Shares Outstanding:
Basic	177,497,862	176,752,714	177,344,481	176,557,889
Diluted	177,835,348	177,012,278	177,647,694	176,762,088
The Connecticut Light and Power Company [Member]
Operating Revenues	673,666	789,249	1,955,361	2,292,146
Operating Expenses:
Fuel, Purchased and Net Interchange Power	257,645	334,230	720,178	987,604
Other Operating Expenses	128,329	127,779	401,899	382,884
Maintenance	36,004	21,056	118,655	75,715
Depreciation	39,711	38,100	117,629	133,568
Amortization of Regulatory Assets/(Liabilities), Net	15,688	32,997	48,736	55,308
Amortization of Rate Reduction Bonds	0	43,778	0	125,985
Taxes Other Than Income Taxes	58,552	59,884	169,745	168,001
Total Operating Expenses	535,929	657,824	1,576,842	1,929,065
Operating Income	137,737	131,425	378,519	363,081
Interest Expense:
Interest on Long-Term Debt	33,326	33,656	100,085	100,918
Interest on Rate Reduction Bonds	0	1,529	0	6,805
Other Interest	1,893	1,496	(815)	4,692
Total Interest Expense	35,219	36,681	99,270	112,415
Other Income/(Loss), Net	(2,356)	6,938	4,308	12,616
Income Before Income Tax Expense	100,162	101,682	283,557	263,282
Income Tax Expense	33,634	32,636	100,057	101,739
Net Income	66,528	69,046	183,500	161,543
Public Service Company of New Hampshire [Member]
Operating Revenues	259,648	276,976	769,309	773,866
Operating Expenses:
Fuel, Purchased and Net Interchange Power	77,939	94,137	234,413	281,161
Other Operating Expenses	52,617	53,133	163,265	172,332
Maintenance	16,208	20,933	64,771	62,560
Depreciation	18,403	17,454	54,432	49,443
Amortization of Regulatory Assets/(Liabilities), Net	17,271	14,513	35,303	(2,809)
Amortization of Rate Reduction Bonds	13,609	12,844	39,748	37,481
Taxes Other Than Income Taxes	15,133	14,191	44,034	40,616
Total Operating Expenses	211,180	227,205	635,966	640,784
Operating Income	48,468	49,771	133,343	133,082
Interest Expense:
Interest on Long-Term Debt	8,484	8,925	25,425	27,705
Interest on Rate Reduction Bonds	1,468	2,320	5,038	7,557
Other Interest	416	208	761	572
Total Interest Expense	10,368	11,453	31,224	35,834
Other Income/(Loss), Net	3,293	3,667	12,112	5,882
Income Before Income Tax Expense	41,393	41,985	114,231	103,130
Income Tax Expense	15,759	13,231	39,468	36,950
Net Income	25,634	28,754	74,763	66,180
Western Massachusetts Electric Company [Member]
Operating Revenues	104,515	103,719	309,589	296,400
Operating Expenses:
Fuel, Purchased and Net Interchange Power	39,194	39,922	112,015	120,274
Other Operating Expenses	22,744	27,314	75,350	73,607
Maintenance	4,001	4,915	12,987	14,825
Depreciation	6,681	5,838	19,644	17,658
Amortization of Regulatory Assets/(Liabilities), Net	3,388	2,735	4,584	445
Amortization of Rate Reduction Bonds	4,071	3,812	12,299	11,534
Taxes Other Than Income Taxes	4,650	4,319	13,395	12,483
Total Operating Expenses	84,729	88,855	250,274	250,826
Operating Income	19,786	14,864	59,315	45,574
Interest Expense:
Interest on Long-Term Debt	4,913	4,691	14,389	13,298
Interest on Rate Reduction Bonds	550	811	1,852	2,623
Other Interest	529	93	785	275
Total Interest Expense	5,992	5,595	17,026	16,196
Other Income/(Loss), Net	(722)	747	259	1,512
Income Before Income Tax Expense	13,072	10,016	42,548	30,890
Income Tax Expense	4,638	2,679	15,977	12,645
Net Income	$ 8,434	$ 7,337	$ 26,571	$ 18,245