The Connecticut Light and Power Company (CNLPM) 10-Q 5 Aug 15 2015 Q2 Quarterly report Financial data

DOCUMENT AND ENTITY INFORMATION

DOCUMENT AND ENTITY INFORMATION - Jun. 30, 2015 - USD ($)	Total
Document And Entity [Line Items]
Entity Registrant Name	Eversource Energy
Document Period End Date	Jun. 30, 2015
Document Type	10-Q
Entity Central Index Key	72,741
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding	317,173,164
Entity Public Float	$ 14,947,688,864
Entity Filer Category	Large Accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Amendment Flag	false
The Connecticut Light And Power Company [Member]
Document And Entity [Line Items]
Entity Registrant Name	The Connecticut Light and Power Company
Entity Central Index Key	23,426
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Public Service Company Of New Hampshire [Member]
Document And Entity [Line Items]
Entity Registrant Name	Public Service Company of New Hampshire
Entity Central Index Key	315,256
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Western Massachusetts Electric Company [Member]
Document And Entity [Line Items]
Entity Registrant Name	Western Massachusetts Electric Company
Entity Central Index Key	106,170
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
NSTAR Electric Company [Member]
Document And Entity [Line Items]
Entity Registrant Name	NSTAR Electric Company
Entity Central Index Key	13,372
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current Assets:
Cash	$ 36,469	$ 38,703
Receivables, Net	903,578	856,346
Unbilled Revenues	205,155	211,758
Taxes Receivable	117,792	337,307
Fuel, Materials and Supplies	289,561	349,664
Regulatory Assets Current	709,660	672,493
Marketable Securities - Current	124,830	124,173
Prepayments and Other Current Assets	62,884	102,021
Total Current Assets	2,449,929	2,692,465
Property, Plant and Equipment, Net	19,079,189	18,647,041
Deferred Debits and Other Assets:
Regulatory Assets Long Term	4,016,684	4,054,086
Goodwill	3,519,401	3,519,401
Marketable Securities	497,919	515,025
Other Long-Term Assets	316,817	349,957
Total Deferred Debits and Other Assets	8,350,821	8,438,469
Total Assets	29,879,939	29,777,975
Current Liabilities:
Notes Payable	953,700	956,825
Long-Term Debt - Current Portion	278,883	245,583
Accounts Payable - Current	598,716	868,231
Regulatory Liability Current	208,510	235,022
Deferred Tax Liabilities Current	203,375	160,288
Other Liabilities - Current	595,801	668,432
Total Current Liabilities	2,838,985	3,134,381
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	4,606,159	4,467,473
Regulatory Liabilities Long-Term	510,807	515,144
Long-Term Derivative Liabilities	380,966	409,632
Accrued Pension, SERP and PBOP	1,636,769	1,638,558
Other Long-Term Liabilities	875,985	874,387
Total Deferred Credits and Other Liabilities	8,010,686	7,905,194
Capitalization:
Long-Term Debt	8,689,647	8,606,017
Noncontrolling Interest in Consolidated Subsidiary:
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	155,568	155,568
Common Shareholders' Equity:
Common Stock	1,669,167	1,666,796
Capital Surplus, Paid In	6,253,411	6,235,834
Retained Earnings	2,644,485	2,448,661
Accumulated Other Comprehensive Loss	(72,033)	(74,009)
Treasury Stock	(309,977)	(300,467)
Common Shareholders' Equity	10,185,053	9,976,815
Total Capitalization	19,030,268	18,738,400
Total Liabilities and Capitalization	29,879,939	29,777,975
The Connecticut Light And Power Company [Member]
Current Assets:
Cash	9,227	2,356
Receivables, Net	395,863	355,140
Accounts Receivable from Affiliated Companies	22,981	16,757
Unbilled Revenues	103,767	102,137
Taxes Receivable	0	116,148
Regulatory Assets Current	263,713	220,344
Materials and Supplies	50,357	46,664
Prepayments and Other Current Assets	15,043	37,822
Total Current Assets	860,951	897,368
Property, Plant and Equipment, Net	6,934,618	6,809,664
Deferred Debits and Other Assets:
Regulatory Assets Long Term	1,461,483	1,475,508
Other Long-Term Assets	146,299	177,568
Total Deferred Debits and Other Assets	1,607,782	1,653,076
Total Assets	9,403,351	9,360,108
Current Liabilities:
Notes Payable To Affiliated Companies	85,600	133,400
Long-Term Debt - Current Portion	0	162,000
Accounts Payable - Current	208,860	272,971
Accounts Payable to Affiliated Companies	58,227	65,594
Obligations to Third Party Suppliers	67,844	73,624
Regulatory Liability Current	122,617	124,722
Deferred Tax Liabilities Current	46,811	34,073
Derivative Liabilities - Current	90,933	88,459
Other Liabilities - Current	97,062	119,347
Total Current Liabilities	777,954	1,074,190
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	1,666,607	1,642,805
Regulatory Liabilities Long-Term	71,245	81,298
Long-Term Derivative Liabilities	380,196	406,199
Accrued Pension, SERP and PBOP	286,131	273,854
Other Long-Term Liabilities	144,983	148,844
Total Deferred Credits and Other Liabilities	2,549,162	2,553,000
Capitalization:
Long-Term Debt	2,975,091	2,679,951
Noncontrolling Interest in Consolidated Subsidiary:
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	116,200	116,200
Common Shareholders' Equity:
Common Stock	60,352	60,352
Capital Surplus, Paid In	1,805,638	1,804,869
Retained Earnings	1,119,702	1,072,477
Accumulated Other Comprehensive Loss	(748)	(931)
Common Shareholders' Equity	2,984,944	2,936,767
Total Capitalization	6,076,235	5,732,918
Total Liabilities and Capitalization	9,403,351	9,360,108
NSTAR Electric Company [Member]
Current Assets:
Cash	2,848	12,773
Receivables, Net	288,581	234,481
Accounts Receivable from Affiliated Companies	50,582	40,353
Unbilled Revenues	41,294	29,741
Taxes Receivable	43,940	144,601
Fuel, Materials and Supplies	56,584	74,179
Regulatory Assets Current	258,489	198,710
Prepayments and Other Current Assets	3,870	10,815
Total Current Assets	746,188	745,653
Property, Plant and Equipment, Net	5,451,668	5,335,436
Deferred Debits and Other Assets:
Regulatory Assets Long Term	1,198,167	1,179,100
Other Long-Term Assets	58,936	73,051
Total Deferred Debits and Other Assets	1,257,103	1,252,151
Total Assets	7,454,959	7,333,240
Current Liabilities:
Notes Payable	377,200	302,000
Long-Term Debt - Current Portion	200,000	4,700
Accounts Payable - Current	173,863	217,311
Accounts Payable to Affiliated Companies	71,066	63,517
Renewable Portfolio Standards Compliance Obligation	61,200	35,698
Regulatory Liability Current	5,007	49,611
Deferred Tax Liabilities Current	107,995	55,136
Other Liabilities - Current	86,718	115,991
Total Current Liabilities	1,140,118	878,788
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	1,538,988	1,527,667
Regulatory Liabilities Long-Term	266,572	262,738
Accrued Pension, SERP and PBOP	220,000	235,529
Other Long-Term Liabilities	123,421	129,279
Total Deferred Credits and Other Liabilities	2,148,981	2,155,213
Capitalization:
Long-Term Debt	1,592,722	1,792,712
Noncontrolling Interest in Consolidated Subsidiary:
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	43,000	43,000
Common Shareholders' Equity:
Common Stock	0	0
Capital Surplus, Paid In	995,378	994,130
Retained Earnings	1,534,500	1,468,955
Accumulated Other Comprehensive Loss	260	442
Common Shareholders' Equity	2,530,138	2,463,527
Total Capitalization	4,165,860	4,299,239
Total Liabilities and Capitalization	7,454,959	7,333,240
Public Service Company Of New Hampshire [Member]
Current Assets:
Cash	818	489
Receivables, Net	84,607	80,151
Accounts Receivable from Affiliated Companies	4,290	3,194
Unbilled Revenues	36,472	40,181
Taxes Receivable	34,985	14,571
Fuel, Materials and Supplies	137,119	148,139
Regulatory Assets Current	88,773	111,705
Prepayments and Other Current Assets	23,538	27,821
Total Current Assets	410,602	426,251
Property, Plant and Equipment, Net	2,714,915	2,635,844
Deferred Debits and Other Assets:
Regulatory Assets Long Term	282,215	293,115
Other Long-Term Assets	34,083	39,228
Total Deferred Debits and Other Assets	316,298	332,343
Total Assets	3,441,815	3,394,438
Current Liabilities:
Notes Payable To Affiliated Companies	133,500	90,500
Accounts Payable - Current	69,884	93,349
Accounts Payable to Affiliated Companies	22,201	33,734
Regulatory Liability Current	5,602	16,044
Deferred Tax Liabilities Current	35,963	36,164
Other Liabilities - Current	30,605	38,969
Total Current Liabilities	297,755	308,760
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	632,890	587,292
Regulatory Liabilities Long-Term	50,250	51,372
Accrued Pension, SERP and PBOP	99,318	93,243
Other Long-Term Liabilities	50,054	50,155
Total Deferred Credits and Other Liabilities	832,512	782,062
Capitalization:
Long-Term Debt	1,076,319	1,076,286
Common Shareholders' Equity:
Common Stock	0	0
Capital Surplus, Paid In	748,635	748,240
Retained Earnings	493,449	486,459
Accumulated Other Comprehensive Loss	(6,855)	(7,369)
Common Shareholders' Equity	1,235,229	1,227,330
Total Capitalization	2,311,548	2,303,616
Total Liabilities and Capitalization	3,441,815	3,394,438
Western Massachusetts Electric Company [Member]
Current Assets:
Cash	1,143	0
Receivables, Net	61,491	51,066
Accounts Receivable from Affiliated Companies	5,507	7,851
Unbilled Revenues	15,912	15,146
Taxes Receivable	1,148	18,126
Regulatory Assets Current	54,926	51,923
Marketable Securities - Current	38,441	28,658
Prepayments and Other Current Assets	5,496	7,607
Total Current Assets	184,064	180,377
Property, Plant and Equipment, Net	1,508,207	1,461,321
Deferred Debits and Other Assets:
Regulatory Assets Long Term	138,138	146,307
Marketable Securities	19,809	29,452
Other Long-Term Assets	27,147	22,018
Total Deferred Debits and Other Assets	185,094	197,777
Total Assets	1,877,365	1,839,475
Current Liabilities:
Notes Payable To Affiliated Companies	60,600	21,400
Long-Term Debt - Current Portion	50,000	50,000
Accounts Payable - Current	36,327	53,732
Accounts Payable to Affiliated Companies	10,217	14,328
Regulatory Liability Current	16,847	22,486
Deferred Tax Liabilities Current	20,822	18,089
Other Liabilities - Current	24,608	24,080
Total Current Liabilities	219,421	204,115
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	422,502	416,822
Regulatory Liabilities Long-Term	12,921	10,835
Accrued Pension, SERP and PBOP	19,530	17,705
Other Long-Term Liabilities	38,065	33,747
Total Deferred Credits and Other Liabilities	493,018	479,109
Capitalization:
Long-Term Debt	578,007	578,471
Common Shareholders' Equity:
Common Stock	10,866	10,866
Capital Surplus, Paid In	391,398	391,256
Retained Earnings	187,673	178,834
Accumulated Other Comprehensive Loss	(3,018)	(3,176)
Common Shareholders' Equity	586,919	577,780
Total Capitalization	1,164,926	1,156,251
Total Liabilities and Capitalization	$ 1,877,365	$ 1,839,475

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Operating Revenues	$ 1,817,061	$ 1,677,614	$ 4,330,491	$ 3,968,204
Operating Expenses:
Purchased Power and Transmission	685,118	624,211	1,847,167	1,602,362
Operations and Maintenance	316,641	373,234	650,024	724,922
Depreciation	163,668	152,207	327,505	303,014
Amortization of Regulatory Assets/(Liabilities), Net	(1,166)	(3,542)	59,438	54,356
Energy Efficiency Programs	101,850	102,711	248,452	241,536
Taxes Other Than Income Taxes	138,935	134,803	288,415	280,335
Total Operating Expenses	1,405,046	1,383,624	3,421,001	3,206,525
Operating Income	412,015	293,990	909,490	761,679
Interest Expense:
Interest on Long-Term Debt	88,021	87,491	175,735	174,868
Other Interest	4,238	5,004	11,367	7,603
Total Interest Expense	92,259	92,495	187,102	182,471
Other Income/(Loss), Net	12,899	5,526	18,626	7,194
Income Before Income Tax Expense	332,655	207,021	741,014	586,402
Income Tax Expense	123,268	77,774	276,494	219,319
Net Income	209,387	129,247	464,520	367,083
Net Income Attributable to Noncontrolling Interests	1,880	1,880	3,759	3,759
Net Income Attributable to Controlling Interests	$ 207,507	$ 127,367	$ 460,761	$ 363,324
Earnings Per Share Basic And Diluted	$ 0.65	$ 0.40	$ 1.45	$ 1.15
Common Stock Dividends Per Share Declared	$ 0.42	$ 0.39	$ 0.84	$ 0.79
Weighted Average Common Shares Outstanding:
Basic	317,613,166	315,950,510	317,352,004	315,742,511
Diluted	318,559,568	317,112,801	318,525,378	317,002,461
The Connecticut Light And Power Company [Member]
Operating Revenues	$ 666,554	$ 587,324	$ 1,471,471	$ 1,321,938
Operating Expenses:
Purchased Power and Transmission	253,180	199,785	586,799	481,165
Operations and Maintenance	118,687	131,762	236,044	241,276
Depreciation	52,191	46,581	105,094	92,712
Amortization of Regulatory Assets/(Liabilities), Net	(7,530)	19,615	40,776	49,546
Energy Efficiency Programs	33,963	35,296	76,770	77,991
Taxes Other Than Income Taxes	62,102	62,159	130,181	129,111
Total Operating Expenses	512,593	495,198	1,175,664	1,071,801
Operating Income	153,961	92,126	295,807	250,137
Interest Expense:
Interest on Long-Term Debt	33,423	34,639	66,904	67,548
Other Interest	2,701	2,831	5,844	4,165
Total Interest Expense	36,124	37,470	72,748	71,713
Other Income/(Loss), Net	4,062	3,130	6,221	4,202
Income Before Income Tax Expense	121,899	57,786	229,280	182,626
Income Tax Expense	43,129	20,401	81,276	65,942
Net Income	78,770	37,385	148,004	116,684
NSTAR Electric Company [Member]
Operating Revenues	617,196	561,513	1,384,004	1,227,701
Operating Expenses:
Purchased Power and Transmission	283,129	242,907	684,995	561,989
Operations and Maintenance	69,430	78,981	145,254	164,905
Depreciation	48,949	46,915	97,716	93,540
Amortization of Regulatory Assets/(Liabilities), Net	(7,336)	(1,517)	(12,901)	14,147
Energy Efficiency Programs	41,733	40,255	97,150	88,584
Taxes Other Than Income Taxes	29,876	32,458	60,841	64,610
Total Operating Expenses	465,781	439,999	1,073,055	987,775
Operating Income	151,415	121,514	310,949	239,926
Interest Expense:
Interest on Long-Term Debt	18,579	19,732	37,225	40,489
Other Interest	(798)	960	1,002	1,263
Total Interest Expense	17,781	20,692	38,227	41,752
Other Income/(Loss), Net	2,533	(246)	3,136	(277)
Income Before Income Tax Expense	136,167	100,576	275,858	197,897
Income Tax Expense	54,204	40,447	110,335	79,681
Net Income	81,963	60,129	165,523	118,216
Public Service Company Of New Hampshire [Member]
Operating Revenues	241,875	211,626	526,722	511,458
Operating Expenses:
Purchased Power and Transmission	47,938	68,349	147,516	183,595
Operations and Maintenance	76,468	70,249	134,895	132,462
Depreciation	25,751	24,464	51,397	48,679
Amortization of Regulatory Assets/(Liabilities), Net	12,050	(20,393)	27,181	(7,831)
Energy Efficiency Programs	3,356	3,292	7,128	7,131
Taxes Other Than Income Taxes	22,249	16,635	41,331	34,348
Total Operating Expenses	187,812	162,596	409,448	398,384
Operating Income	54,063	49,030	117,274	113,074
Interest Expense:
Interest on Long-Term Debt	11,359	11,390	22,758	22,916
Other Interest	303	(391)	177	55
Total Interest Expense	11,662	10,999	22,935	22,971
Other Income/(Loss), Net	1,245	946	1,628	1,212
Income Before Income Tax Expense	43,646	38,977	95,967	91,315
Income Tax Expense	15,701	14,897	35,977	34,597
Net Income	27,945	24,080	59,990	56,718
Western Massachusetts Electric Company [Member]
Operating Revenues	125,194	108,289	278,058	245,698
Operating Expenses:
Purchased Power and Transmission	43,055	37,619	112,716	87,050
Operations and Maintenance	20,104	23,686	39,889	46,265
Depreciation	10,848	10,317	21,223	20,638
Amortization of Regulatory Assets/(Liabilities), Net	3,336	343	7,264	741
Energy Efficiency Programs	9,519	10,249	20,594	22,114
Taxes Other Than Income Taxes	9,398	8,396	18,833	16,479
Total Operating Expenses	96,260	90,610	220,519	193,287
Operating Income	28,934	17,679	57,539	52,411
Interest Expense:
Interest on Long-Term Debt	6,015	6,104	12,060	12,165
Other Interest	276	603	1,052	188
Total Interest Expense	6,291	6,707	13,112	12,353
Other Income/(Loss), Net	1,245	594	1,819	1,168
Income Before Income Tax Expense	23,888	11,566	46,246	41,226
Income Tax Expense	9,693	4,548	18,807	16,106
Net Income	$ 14,195	$ 7,018	$ 27,439	$ 25,120

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net Income	$ 209,387	$ 129,247	$ 464,520	$ 367,083
Other Comprehensive Income Loss Net Of Tax Period Increase Decrease Abstract
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	509	510	1,018	1,019
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	(1,248)	218	(1,116)	458
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	1,120	2,086	2,074	3,047
Other Comprehensive Income (Loss), Net of Tax, Total	381	2,814	1,976	4,524
Comprehensive Income Attributable to Noncontrolling Interests	(1,880)	(1,880)	(3,759)	(3,759)
Comprehensive Income	207,888	130,181	462,737	367,848
The Connecticut Light And Power Company [Member]
Net Income	78,770	37,385	148,004	116,684
Other Comprehensive Income Loss Net Of Tax Period Increase Decrease Abstract
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	111	111	222	222
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	(43)	7	(39)	15
Other Comprehensive Income (Loss), Net of Tax, Total	68	118	183	237
Comprehensive Income	78,838	37,503	148,187	116,921
NSTAR Electric Company [Member]
Net Income	81,963	60,129	165,523	118,216
Other Comprehensive Income Loss Net Of Tax Period Increase Decrease Abstract
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	(2)		(182)
Other Comprehensive Income (Loss), Net of Tax, Total	(2)		(182)
Comprehensive Income	81,961	60,129	165,341	118,216
Public Service Company Of New Hampshire [Member]
Net Income	27,945	24,080	59,990	56,718
Other Comprehensive Income Loss Net Of Tax Period Increase Decrease Abstract
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	290	291	581	581
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	(75)	12	(67)	26
Other Comprehensive Income (Loss), Net of Tax, Total	215	303	514	607
Comprehensive Income	28,160	24,383	60,504	57,325
Western Massachusetts Electric Company [Member]
Net Income	14,195	7,018	27,439	25,120
Other Comprehensive Income Loss Net Of Tax Period Increase Decrease Abstract
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	84	84	169	169
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	(12)	2	(11)	4
Other Comprehensive Income (Loss), Net of Tax, Total	72	86	158	173
Comprehensive Income	$ 14,267	$ 7,104	$ 27,597	$ 25,293

CONSOLIDATED STATEMENT OF CASH

CONSOLIDATED STATEMENT OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Operating Activities:
Net Income	$ 464,520	$ 367,083
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:
Depreciation	327,505	303,014
Deferred Income Tax Expense (Benefit)	176,800	133,149
Pension, SERP and PBOP Expense	48,432	47,558
Pension and PBOP Contributions	(31,032)	(40,640)
Regulatory Over/(Under) Recoveries, Net	(73,547)	164,388
Amortization of Regulatory Assets/(Liabilities), Net	59,438	54,356
Proceeds from DOE Damages Claim, Net	0	125,658
Other	(48,247)	(9,359)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(123,984)	(57,570)
Increase Decrease in Fuel, Materials and Supplies	60,044	26,633
Taxes Receivable/(Accrued)	214,577	(62,900)
Accounts Payable	(228,176)	(112,954)
Other Current Assets and Liabilities, Net	9,226	(41,753)
Net Cash Flows Provided by Operating Activities	855,556	896,663
Investing Activities:
Investments in Property, Plant and Equipment	(740,379)	(724,043)
Proceeds from Sales of Marketable Securities	427,990	256,309
Purchases of Marketable Securities	(408,242)	(257,168)
Other Investing Activities	4,821	3,473
Net Cash Flows Used in Investing Activities	(715,810)	(721,429)
Financing Activities:
Cash Dividends on Common Stock	(264,936)	(237,161)
Cash Dividends on Preferred Stock	(3,759)	(3,759)
Increase/(Decrease) in Short-Term Debt	(449,375)	(213,000)
Issuance of Long-Term Debt	750,000	650,000
Retirements of Long-Term Debt	(166,577)	(376,650)
Other Financing Activities	(7,333)	(3,932)
Net Cash Flows Provided by/(Used in) Financing Activities	(141,980)	(184,502)
Net Increase/(Decrease) in Cash	(2,234)	(9,268)
Cash - Beginning of Year	38,703	43,364
Cash - End of Year	36,469	34,096
The Connecticut Light And Power Company [Member]
Operating Activities:
Net Income	148,004	116,684
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:
Depreciation	105,094	92,712
Deferred Income Tax Expense (Benefit)	30,145	43,253
Pension, SERP and PBOP Expense, Net of Contributions	7,079	5,973
Regulatory Over/(Under) Recoveries, Net	(55,302)	18,156
Amortization of Regulatory Assets/(Liabilities), Net	40,776	49,546
Proceeds from DOE Damages Claim		65,370
Other	(2,432)	(3,428)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(73,279)	(129,209)
Taxes Receivable/(Accrued)	123,051	27,679
Accounts Payable	(55,192)	(26,995)
Other Current Assets and Liabilities, Net	2,085	15,705
Net Cash Flows Provided by Operating Activities	270,029	275,446
Investing Activities:
Investments in Property, Plant and Equipment	(242,346)	(221,365)
Other Investing Activities	(1,362)	1,575
Net Cash Flows Used in Investing Activities	(243,708)	(219,790)
Financing Activities:
Cash Dividends on Common Stock	(98,000)	(85,600)
Cash Dividends on Preferred Stock	(2,779)	(2,779)
Issuance of Long-Term Debt	300,000	250,000
Increase/(Decrease) in Notes Payable to Affiliate	(47,800)	(280,900)
Retirements of Long-Term Debt	(162,000)
Capital Contributions from NU Parent	0	70,000
Other Financing Activities	(8,871)	(3,128)
Net Cash Flows Provided by/(Used in) Financing Activities	(19,450)	(52,407)
Net Increase/(Decrease) in Cash	6,871	3,249
Cash - Beginning of Year	2,356	7,237
Cash - End of Year	9,227	10,486
NSTAR Electric Company [Member]
Operating Activities:
Net Income	165,523	118,216
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:
Depreciation	97,716	93,540
Deferred Income Tax Expense (Benefit)	61,734	(21,724)
Pension, SERP and PBOP Expense, Net of Contributions	(264)	(8,281)
Regulatory Over/(Under) Recoveries, Net	(96,290)	63,955
Amortization of Regulatory Assets/(Liabilities), Net	(12,901)	14,147
Proceeds from DOE Damages Claim		29,113
Other	(28,653)	(16,870)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(81,524)	(31,746)
Increase Decrease in Fuel, Materials and Supplies	17,595	(7,399)
Taxes Receivable/(Accrued)	100,661	65,692
Accounts Payable	(38,388)	(21,511)
Accounts Payable Related Parties	(2,680)	107,363
Other Current Assets and Liabilities, Net	25,076	3,158
Net Cash Flows Provided by Operating Activities	207,605	387,653
Investing Activities:
Investments in Property, Plant and Equipment	(188,103)	(213,508)
Other Investing Activities	53	576
Net Cash Flows Used in Investing Activities	(188,050)	(212,932)
Financing Activities:
Cash Dividends on Common Stock	(99,000)	(253,000)
Cash Dividends on Preferred Stock	(980)	(980)
Increase/(Decrease) in Short-Term Debt	75,200	91,000
Issuance of Long-Term Debt	0	300,000
Retirements of Long-Term Debt	(4,700)	(301,650)
Other Financing Activities	0	(5,137)
Net Cash Flows Provided by/(Used in) Financing Activities	(29,480)	(169,767)
Net Increase/(Decrease) in Cash	(9,925)	4,954
Cash - Beginning of Year	12,773	8,021
Cash - End of Year	2,848	12,975
Public Service Company Of New Hampshire [Member]
Operating Activities:
Net Income	59,990	56,718
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:
Depreciation	51,397	48,679
Deferred Income Tax Expense (Benefit)	47,454	61,093
Pension, SERP and PBOP Expense	2,359	2,416
Regulatory Over/(Under) Recoveries, Net	(3,089)	18,849
Amortization of Regulatory Assets/(Liabilities), Net	27,181	(7,831)
Proceeds from DOE Damages Claim		13,103
Other	6,367	4,386
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(6,597)	3,500
Increase Decrease in Fuel, Materials and Supplies	11,019	8,013
Taxes Receivable/(Accrued)	(20,414)	(55,243)
Accounts Payable	(21,362)	(7,146)
Other Current Assets and Liabilities, Net	(3,792)	(4,166)
Net Cash Flows Provided by Operating Activities	150,513	142,371
Investing Activities:
Investments in Property, Plant and Equipment	(140,171)	(117,387)
Other Investing Activities	169	(101)
Net Cash Flows Used in Investing Activities	(140,002)	(117,488)
Financing Activities:
Cash Dividends on Common Stock	(53,000)	(33,000)
Increase/(Decrease) in Notes Payable to Affiliate	43,000	8,500
Other Financing Activities	(182)	(176)
Net Cash Flows Provided by/(Used in) Financing Activities	(10,182)	(24,676)
Net Increase/(Decrease) in Cash	329	207
Cash - Beginning of Year	489	130
Cash - End of Year	818	337
Western Massachusetts Electric Company [Member]
Operating Activities:
Net Income	27,439	25,120
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:
Depreciation	21,223	20,638
Deferred Income Tax Expense (Benefit)	12,503	15,234
Regulatory Over/(Under) Recoveries, Net	(7,911)	28,115
Amortization of Regulatory Assets/(Liabilities), Net	7,264	741
Proceeds from DOE Damages Claim		18,073
Other	(3,598)	1,462
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(11,593)	44,859
Taxes Receivable/(Accrued)	18,774	(19,555)
Accounts Payable	(21,056)	(26,494)
Other Current Assets and Liabilities, Net	859	(11,587)
Net Cash Flows Provided by Operating Activities	43,904	96,606
Investing Activities:
Investments in Property, Plant and Equipment	(62,966)	(61,470)
Proceeds from Sales of Marketable Securities	49,739	44,449
Purchases of Marketable Securities	(50,118)	(44,754)
Net Cash Flows Used in Investing Activities	(63,345)	(61,775)
Financing Activities:
Cash Dividends on Common Stock	(18,600)	(49,000)
Increase/(Decrease) in Notes Payable to Affiliate	39,200	15,900
Other Financing Activities	(16)	(22)
Net Cash Flows Provided by/(Used in) Financing Activities	20,584	(33,122)
Net Increase/(Decrease) in Cash	1,143	1,709
Cash - Beginning of Year	0	0
Cash - End of Year	$ 1,143	$ 1,709

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Significant Accounting Policies [Text Block]	EVERSOURCE ENERGY AND SUBSIDIARIES THE CONNECTICUT LIGHT AND POWER COMPANY NSTAR E LECTRIC COMPANY AND SUBSIDIARY PUBLIC SERVICE COMPANY O F NEW HAMPSHIRE AND SUBSIDIARY WESTERN MASSACHUSETTS ELECTRIC COMPANY COMBINED NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) Refer to the Glossary of Terms included in this combined Quarterly Report on Form 10- Q for abbreviations and acronyms used throughout the combined notes to the unaudited condensed consolidated financial statements. 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES A . Basis of Presentation Eversource Energy is a public utility holding company primarily engaged through its wholly owned regulated utility subsidiaries in the energy delivery business. Eversource Energy 's wholly owned regulat ed utility subsidiaries consist of CL&P, NSTAR Electric, PSNH, WMECO, Yankee Gas and NSTAR Gas. Eversource provides energy deliv ery service to approximately 3.6 million electric and natural gas customers through these six regulated utilities in Connecticut, Ma ss achusetts and New Hampshire . On April 30 , 2015, the Company's legal name was changed from Northeast Utilities to Eversource Energy. CL&P, NSTAR Electric, PSNH and WMECO are each doing business as Eversource Energy. The unaudited condensed consolidated financial stateme nts of Eversource , NSTAR Electric and PSNH include the accounts of each o f their respective subsidiaries. Intercompany transactions have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements of Eversource , NSTAR Electric and PSNH and the unaudited condensed financial statements of CL&P and WMECO are herein collectively referred to as the "financial statements." The combined notes to the financial statements have been prepared pursuant to the rules and regulations of the SEC. Certain information and footnote disclosures included in annual financial statements prepared in accordance with GAAP have been omitted pursuant to such rules and regulations. The accompanying financial statements should be read in conjunction with the entirety of this combine d Quarterly Report on Form 10 -Q , the first quarter 2015 combine d Quarterly Report on Form 10 -Q and the 2014 combined Annual Report on Form 10 -K of Eversource , CL&P, NSTAR Electric, PS NH and WMECO, which were filed with the SEC. The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The financial statements contain, in the opinion of management, all adjustments (including normal, recurring adjustments) necessary to present fairly Eversource 's, CL&P's, NSTAR Electric's, PSNH's and WMECO's financial position as of June 30 , 2015 and December 31, 2014, the results of operations and comprehensive income for the three and six months ended June 30 , 2015 and 2014 , and the cash flows for the six months ended June 30, 2015 and 2014 . The results of operations and comprehensive income for the three and six months ended June 30 , 2015 and 2014 and the cash flows for the six months ended June 30, 2015 and 2014 are not necessarily indicative of the results expected for a full year. Eversource consolidates CYAPC and YAEC because CL&P's, NSTAR Electric's, PSNH's and WMECO's combined ownership interest in each of these entities is greater than 50 percent. Intercompany transactions between CL&P, NSTAR Electric, PSNH and WMECO and the CYAPC and YAEC companies have been eliminated in consolidation of the Eversource financial statements. Eversource 's utility subsidiaries ' distribution (including generation ) and transmission businesses and NPT are subject to rate-regulation that is based on cost recovery and meets the criteria for application of accounting guidance for entities with rate-regulated operations , which considers the effect of regulation on the d ifferences in the timing of the recognition of certain revenues and expenses from those of other businesses and industries. See Note 2, "Regulatory Accounting," for further information. Certain reclassifications of prior period data were made in the accompanying financial statements to conform to the current period presentation . B. Accounting Standards Accounting Standards Issued but not Yet Effective : In May 2014, the Financial Accounting Standards Board ( FASB ) issued ASU 2014-09, Revenue from Contracts with Customers , which amends existing revenue recognition guidance and is required to be applied retrospectively (either to each reporting period presented or cumulatively at the date of initial application). On July 9, 2015 , the FASB deferred the effective date of the new revenue standard by one year. The Company will implement the standard beginning in the first quarter of 2018. Management is reviewing the requirements of the ASU. The ASU is not expected to have a material impact on the financial statements of Eversource , CL&P, NSTAR Electric, PSNH and WMECO . In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs , that changes the balance sheet presentation of debt issuance costs. Under the new standard, issuance costs related to debt will be presented on the balance sheet as a direct deduction from the carrying amount of the debt liability rather than as a deferred cost as required by current guidance . The new accounting guidance is effective for interim and annual periods beginning in the first quarter of 2016 with early adoption permitted. Upon adoption, an entity must apply the new guidance retrospectively to all prior periods presented in the financial statements. Management does not expect the adoption of this standard to have a material effect on the financial statements of Eversource , CL&P, NSTAR Electric, PSNH and WMECO . C . Provision for Uncollectible Accounts Eversource, including CL&P, NSTAR Electric, PSNH and WMECO, presents its receivables at estimated net realizable value by maintaining a provision for uncollectible accounts. This provision is determined based upon a variety of judgments and factors, including the application of an estimated uncollectible percentage to each receivable aging category. The estimate is based upon historical collection and write-off experience and management's assessment of collectability from customers. Management continuously assesses the collectability of receivables and adjusts collectability estimates based on actual experience. Receivable balances are written off against the provision for uncollectible accounts when the accounts are terminated and these balances are deemed to be uncollectible. The PURA allows CL&P and Yankee Gas to accelerate the recovery of accounts receivable balances attributable to qualified customers under financial or medical duress (uncollectible hardship accounts receivable) outstanding for greater than 90 days. The DPU allows WMECO to also recover in rates amounts associated with certain uncollectible hardship accounts receivable. Uncollectible customer account balances, which are expected to be recovered in rates, are included in Regulatory Assets or Other Long-Term Assets. The total provision for uncollectible accounts and for uncollectible hardship accounts , which is included in the total provision, are included in Recei vables, Net on the balance sheets, and were as follows: Total Provision for Uncollectible Accounts Uncollectible Hardship (Millions of Dollars) As of June 30, 2015 As of December 31, 2014 As of June 30, 2015 As of December 31, 2014 Eversource $ 209.8 $ 175.3 $ 106.2 $ 91.5 CL&P 100.5 84.3 84.7 74.0 NSTAR Electric 46.3 40.7 - - PSNH 9.5 7.7 - - WMECO 12.1 9.9 7.2 6.2 D . Fair Value Measurements Fair value measurement guidance is applied to derivative contracts that are not elected or designated as "normal purchases or normal sales" (normal) and to the marketable securities held in trusts. Fair value measurement guidanc e is also applied to valuations of the investments used to calculate the funded status of pension and PBOP plans and nonrecurring fair value measurements of nonfinancial ass ets such as goodwill and AROs, and is also used to estimate the fair value of preferred stock and long-term debt. Fair Value Hierarchy: In measuring fair value, Eversource uses observabl e market data when available in order to minimize the use of unobservable inputs. Inputs used in fair value measurements are categorized into three fair value hierarchy levels for disclosure purposes. The entire fair value measurement is categorized based on the lowest level of input that is significant to the fair value measurement. Eversource evaluates the classification of assets and liabilities measured at fair value on a quarterly basis, and Eversource ' s policy is to recognize transfers between levels of the fair value hierarchy as of the end of the reporting period. The three levels of the fair value hierarchy are described below: Level 1 - Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2 - Inputs are quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs are observable. Level 3 - Quoted market prices are not available. Fair value is derived from valuation techniques in which one or more significant inputs or assumptions are unobservable. Where possible, valuation techniques incorporate observable market inputs that can be validated to external sources such as industry exchanges, including prices of energy and energy-related products. Determination of Fair Value: The valuation techniques and inputs used in Eversource 's fair value measurements are described in Note 4 , "Derivative Instruments," Note 5 , "Marketable Securities," and Note 9 , "Fair Value of Financial Instruments," to the financial statements. E . Other Income, Net Items included within Other Income, Net on the statements of income primarily consist of investment income /( loss), interest income, AFUDC related to equity funds , and equity in earnings. Investment incom e /( loss) primarily relates to debt and equity securities held in trust . For further information, see Note 5, "Marketable Securities," to the financial statements. F . Other Taxes Gross receipts taxes levied by the state of Connecticut are collected by CL&P and Yankee Gas from their respective customers. These gross receipts taxes are shown separately with collections in Operating Revenues and payments in Taxes Other Than I ncome Taxes on the statements of income as follows : For the Three Months Ended For the Six Months Ended (Millions of Dollars) June 30, 2015 June 30, 2014 June 30, 2015 June 30, 2014 Eversource $ 33.2 $ 35.2 $ 75.1 $ 79.6 CL&P 29.5 30.9 62.5 66.5 Certain sales taxes are collected by Eversource 's companies that s erve customers in Connecticut and Massachusetts as agents for state and local governments and are recorded on a net basis with no impact on the statements of income . G. Supplemental Cash Flow Information Non-cash investing activities include plant additions included in Accounts Payable as follows: (Millions of Dollars) As of June 30, 2015 As of June 30, 2014 Eversource $ 142.3 $ 125.5 CL&P 47.2 54.0 NSTAR Electric 29.5 21.6 PSNH 25.6 14.8 WMECO 13.7 9.9 H. Severance Benefits E versource rec orded severance benefit expense of $ 1.2 million and $ 1.4 million for the three months ended June 30, 2015 and 2014 , respectively, and $ 1.6 million and $ 5.7 million for the six months ended June 30, 2015 and 2014, respectively, in connection with reorganizational and cost saving initiatives, and, in 2014, the partial outsourcing of information technology functions . As of June 30 , 2015 and December 31, 2014 , the severance accrual totaled $ 7.8 million and $ 10.4 million , respectively, and was included in Other Current Liabilities on the balance sheet s .

REGULATORY ACCOUNTING

REGULATORY ACCOUNTING	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Public Utilities Disclosure [Text Block]	2 . REGULATORY ACCOUNTING Eversource's Regulated companies are subject to rate-regulation that is based on cost recovery and meets the criteria for application of accounting guidance for rate-regulated operations , which consider the effect of regulation o n the timing of the recognition of certain revenues and expenses . The Regulated companies' financial statements reflect the effects of the rate-making process. The ra tes charged to the customers of Eversource 's Regulated companies are designed to collect each company's costs to provide service, including a return on investment. Management believes it is probable that each of the Regulated companies will recover their respective investments in long-lived assets, including regulatory assets. If management were to determine that it could no longer apply the accounting guidance applicable to rate-regulated enterprises to any of the Regulated companies' operations, or that management could not conclude it is probable that costs would be recovered from customers in future rates, the costs would be charged to net income in the period in which the determination is made. Regulatory Assets: The components of regulatory assets are as follows: As of June 30, 2015 As of December 31, 2014 (Millions of Dollars) Eversource Eversource Benefit Costs $ 1,980.0 $ 2,016.0 Derivative Liabilities 423.7 425.5 Income Taxes, Net 631.5 635.3 Storm Restoration Costs 484.3 502.8 Goodwill-related 495.1 505.4 Regulatory Tracker Mechanisms 430.7 350.5 Contractual Obligations - Yankee Companies 124.8 123.8 Other Regulatory Assets 156.3 167.3 Total Regulatory Assets 4,726.4 4,726.6 Less: Current Portion 709.7 672.5 Total Long-Term Regulatory Assets $ 4,016.7 $ 4,054.1 As of June 30, 2015 As of December 31, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH WMECO CL&P Electric PSNH WMECO Benefit Costs $ 443.3 $ 496.1 $ 175.1 $ 85.9 $ 445.4 $ 515.9 $ 174.3 $ 85.0 Derivative Liabilities 420.2 2.2 - - 410.9 4.5 - - Income Taxes, Net 438.9 84.0 34.8 30.7 437.7 83.7 38.0 35.5 Storm Restoration Costs 298.4 117.1 41.1 27.7 319.6 103.7 47.7 31.8 Goodwill-related - 425.1 - - - 433.9 - - Regulatory Tracker Mechanisms 44.8 255.0 84.3 36.0 16.1 141.4 103.5 33.0 Other Regulatory Assets 79.6 77.2 35.7 12.7 66.1 94.7 41.3 12.9 Total Regulatory Assets 1,725.2 1,456.7 371.0 193.0 1,695.8 1,377.8 404.8 198.2 Less: Current Portion 263.7 258.5 88.8 54.9 220.3 198.7 111.7 51.9 Total Long-Term Regulatory Assets $ 1,461.5 $ 1,198.2 $ 282.2 $ 138.1 $ 1,475.5 $ 1,179.1 $ 293.1 $ 146.3 Regulatory Costs in Other Long-Term Assets : T he Regulated companies had $ 60.8 million ($ 1.9 million for CL&P , $ 21.9 million for NSTAR Electric , $ 2 million for PSNH and $ 15.4 million for WMECO) and $ 60.5 million ($ 1.3 million for CL&P, $ 33. 2 million for NSTAR Electric , $0.9 million for PSNH, and $ 11 million for WMECO) of additional regulatory costs as of June 30 , 2015 and December 31, 201 4 , respectively, that were included in Other Long- Term Assets on the balance sheets. These amounts represent incurred costs for which recovery has not yet been specifically approved by the applicable regulatory agency. However, based on regulatory policies or past precedent on similar costs, m anagement believes it is probable that these costs will ultimately be approved and recovered from customers in rates . The NSTAR Electric balance as of June 30 , 2015 and December 31, 2014 primarily related to costs deferred in connection with the basic ser vice bad debt adder. See Note 8 D , "Commitments and Contingencies – Basic Service Bad Debt Adder," for further information. Regulatory Liabilities: The components of regulatory liabilities are as follows: As of June 30, 2015 As of December 31, 2014 (Millions of Dollars) Eversource Eversource Cost of Removal $ 434.9 $ 439.9 Regulatory Tracker Mechanisms 198.0 192.3 AFUDC - Transmission 66.2 67.1 Other Regulatory Liabilities 20.2 50.8 Total Regulatory Liabilities 719.3 750.1 Less: Current Portion 208.5 235.0 Total Long-Term Regulatory Liabilities $ 510.8 $ 515.1 As of June 30, 2015 As of December 31, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH WMECO CL&P Electric PSNH WMECO Cost of Removal $ 13.5 $ 261.5 $ 49.1 $ 2.8 $ 19.7 $ 258.3 $ 50.3 $ 1.1 Regulatory Tracker Mechanisms 115.6 2.9 4.8 17.0 122.6 20.7 14.2 22.3 AFUDC - Transmission 52.2 5.0 - 9.0 53.6 4.4 - 9.1 Other Regulatory Liabilities 12.5 2.2 2.0 0.9 10.1 28.9 2.9 0.8 Total Regulatory Liabilities 193.8 271.6 55.9 29.7 206.0 312.3 67.4 33.3 Less: Current Portion 122.6 5.0 5.6 16.8 124.7 49.6 16.0 22.5 Total Long-Term Regulatory Liabilities $ 71.2 $ 266.6 $ 50.3 $ 12.9 $ 81.3 $ 262.7 $ 51.4 $ 10.8 2015 Regulatory Developments: FERC ROE Complaints: As a result of the March 3, 2015 FERC order in the pending ROE complaint proceedings described in Note 8 C, "Commitment s and Contingencies – FERC ROE Complaints , " in 2015, Eversource recognized a pre-tax charge to earnings (excluding interest) of $20 million, of which $12.5 million was recorded at CL&P, $2.4 million at NSTAR Electric, $1 million at PSNH, and $4.1 million at WMECO. The pre-tax charge was recorded as a regulatory liability and as a reduction to Operating Revenues. NSTAR Electric and NSTAR Gas 2014 Comprehensive Settlement Agreement : On March 2, 2015, the DPU approved the comprehensive settlement agreement between NSTAR Electric, NSTAR Gas and the Massachusetts Attorney General (the " Settlement " ) as filed with the DPU on December 31, 2014. The Settlement resolved the outstanding NSTAR Electric CPSL program filings for 2006 through 2011, the NSTAR Electric and NSTAR Gas PAM and energy efficiency-related customer billing adjustments reported in 2012, and the recovery of LBR related to NSTAR Electric ' s energy efficiency programs for 2009 through 2011 (11 dockets in total). In 2015, as a result of the DPU order, NSTAR Electric and NSTAR Gas commenced refunding a combined $44.7 million to customers, which was recorded as a regulatory liability. NSTAR Electric recognized a $21.7 million pre-tax benefit in the first half of 2015 as a result of the approval of the Settlement . NSTAR Electric Basic Service Bad Debt Adder : On January 7, 2015, the DPU issued an order concluding that NSTAR Electric had removed energy-related bad debt costs from base distribution rates effective January 1, 2006. The DPU ordered NSTAR Electric and the Massachusetts Attorney General to collaborate on the reconciliations of energy-related bad debt costs through 2014. As a result of the DPU order, NSTAR Electric increased its regulatory assets and reduced operations and maintenance expense by $24.2 million in the first quarter, resulting in after-tax earnings of $14.5 million. On May 5, 2015, NSTAR Electric filed for recovery of the energy-related bad debt costs regulatory asset from customers beginning July 1, 2015. On June 24, 2015, the DPU delayed the effective date of NSTAR Electric's proposed rate increase from July 1, 2015 to November 1, 2015 to allow for the DPU staff to review the reconciliations. The established procedural schedule is expected to result in an approval of the proposed rate increase in the fourth quarter of 2015. CL&P Distribution Rates : On December 17, 2014, PURA granted a re-opener request to CL&P's base distribution rate application for further review of the appropriate balance of ADIT utilized in the calculation of rate base. On July 2, 2015, PURA issued a final order that approved a settlement agreement filed on May 19, 2015 between CL&P and the PURA Prosecutorial Staff. The order allows for an increase to rate base of approximately $166 million associated with ADIT, including a regulatory asset to recover the incremental revenue requirement for the period December 1, 2014 through November 30, 2015 over a subsequent two-year period. The rate base increase provided an increase to total allowed annual revenue requirements of $18.4 million beginning December 1, 2014. Of that amount, $10.7 million has been recorded as a regulatory asset in June 2015, with a corresponding increase in Operating Revenues. The remaining $7.7 million will be recorded from July 2015 through November 2015. The aggregate amount will be collected from customers in rates over a 24-month period commencing on December 1, 2015.

PROPERTY, PLANT AND ACCUMULATED

PROPERTY, PLANT AND ACCUMULATED DEPRECIATION	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Property Plant And Equipment Disclosure [Text Block]	3. PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION The following tables summarize the investments in utility property, plant and equipment by asset category : As of June 30, 2015 As of December 31, 2014 (Millions of Dollars) Eversource Eversource Distribution - Electric $ 12,701.6 $ 12,495.2 Distribution - Natural Gas 2,625.9 2,595.4 Transmission 7,196.3 6,930.7 Generation 1,175.9 1,170.9 Electric and Natural Gas Utility 23,699.7 23,192.2 Other (1) 547.5 551.3 Property, Plant and Equipment, Gross 24,247.2 23,743.5 Less: Accumulated Depreciation Electric and Natural Gas Utility (5,950.4) (5,777.8) Other (238.4) (231.8) Total Accumulated Depreciation (6,188.8) (6,009.6) Property, Plant and Equipment, Net 18,058.4 17,733.9 Construction Work in Progress 1,020.8 913.1 Total Property, Plant and Equipment, Net $ 19,079.2 $ 18,647.0 (1) These assets are primarily comprised of building improvements , computer software , hardware and equipment and telecommunications assets at Eversource S ervice and Eversource's unregulated companies . As of June 30, 2015 As of December 31, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH WMECO CL&P Electric PSNH WMECO Distribution $ 5,245.3 $ 4,954.7 $ 1,744.8 $ 796.8 $ 5,158.8 $ 4,895.5 $ 1,696.7 $ 784.2 Transmission 3,455.5 1,965.2 821.2 906.4 3,274.0 1,928.5 789.7 891.0 Generation - - 1,141.5 34.4 - - 1,136.5 34.4 Property, Plant and Equipment, Gross 8,700.8 6,919.9 3,707.5 1,737.6 8,432.8 6,824.0 3,622.9 1,709.6 Less: Accumulated Depreciation (1,975.9) (1,824.9) (1,127.6) (309.2) (1,928.0) (1,761.4) (1,090.0) (297.4) Property, Plant and Equipment, Net 6,724.9 5,095.0 2,579.9 1,428.4 6,504.8 5,062.6 2,532.9 1,412.2 Construction Work in Progress 209.7 356.7 135.0 79.8 304.9 272.8 102.9 49.1 Total Property, Plant and Equipment, Net $ 6,934.6 $ 5,451.7 $ 2,714.9 $ 1,508.2 $ 6,809.7 $ 5,335.4 $ 2,635.8 $ 1,461.3 As of June 30, 2015, PSNH had $ 1.1 billion in gross generation utility plant assets and Accumulated Depreciation of $ 505.6 million. These generation assets are the subject of a divestiture agreement entered into on June 10 , 2015 between Eversource, PSNH and key New Hampshire officials whereby, among other resolutions, PSNH has agreed to sell these generation assets. Upon completion of the sale, all remaining stranded costs will be recovered via bonds that will be secured by a non- bypassable charge on the bills of PSNH's customers . See Note 8 E , “Commitments and Contingencies – PSNH Generation Restructuring,” for further information.

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS	6 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Derivative Instruments and Hedging Activities Disclosure [Text Block]	4 . DERIVATIVE INSTRUMENTS The Regulated companies purchase and procure energy and energy-related products , which are subject to price volatility, for their customers . The costs associated with supplying energy to customers are recoverable from customer s, in future rates. The Regulated companies manage the risks associated with the price volatility of energy and energy-related products through the use of derivative and nonderivative contracts. Many of the derivative contracts meet the definition of, and are designated as, normal and qualify for accrual accounting under the applicable accounting guidance. The costs and benefits of derivative contracts that meet the definition of normal are recognized in Operating Expenses or Operating Revenues on the statements of income, as applicable, as electricity or natural gas is delivered. Derivative contracts that are not designated as normal are recorded at fair value as current or long-term Derivative Assets or Derivative Liabilities on the balance sheets. For the Regulated companies, regulatory assets or regulatory liabilities are recorded to offset the fair values of derivatives, as contract settlement amount s are recovered from, or refunded to, customers in their respective energy supply rates. The gross fair values of derivative assets and liabilities with the same counterparty are offset and reported as net Derivative Assets or Derivative Liabilities, with current and long-term portions, on the balance sheets. The following table present s the gross fair values of contracts categorized by risk type and the net amount recorded as current or long-term derivative asset or liability: As of June 30, 2015 As of December 31, 2014 Commodity Supply Net Amount Commodity Supply Net Amount and Price Risk Recorded as and Price Risk Recorded as (Millions of Dollars) Management Netting (1) a Derivative Management Netting (1) a Derivative Current Derivative Assets: Level 3: Eversource $ 16.5 $ (10.4) $ 6.1 $ 16.2 $ (6.6) $ 9.6 CL&P 16.5 (10.4) 6.1 16.1 (6.6) 9.5 NSTAR Electric - - - 0.1 - 0.1 Long-Term Derivative Assets: Level 3: Eversource $ 69.1 $ (23.9) $ 45.2 $ 93.5 $ (19.2) $ 74.3 CL&P 68.7 (23.9) 44.8 93.5 (19.2) 74.3 NSTAR Electric 0.4 - 0.4 - - - Current Derivative Liabilities: Level 2: Eversource $ (1.5) $ 0.2 $ (1.3) $ (9.8) $ - $ (9.8) Level 3: Eversource (92.7) - (92.7) (90.0) - (90.0) CL&P (90.9) - (90.9) (88.5) - (88.5) NSTAR Electric (1.8) - (1.8) (1.5) - (1.5) Long-Term Derivative Liabilities: Level 2: Eversource $ - $ - $ - $ (0.3) $ - $ (0.3) Level 3: Eversource (381.0) - (381.0) (409.3) - (409.3) CL&P (380.2) - (380.2) (406.2) - (406.2) NSTAR Electric (0.8) - (0.8) (3.1) - (3.1) (1) Amounts represent derivativ e assets and liabilities that Eversource elected to record net on the balance sheets. These amounts are subject to master netting agreements or similar agreements for which the right of offset exists. For further information on the fair value of d erivative contracts, see Note 1 D , "Summary of Significant Accounting Policies - Fair Value Measurements ," to the financial statements. Deri vative Contract s at Fair Value with Offsetting Regulatory Amounts Commodity Supply and Price Risk Management : As required by regulation, CL&P , along with UI, has capacity-related contracts with generation facilities. CL&P has a sharing agreement with UI, with 80 percent of each contract allocated to CL&P and 20 percent allocated to UI. The combined capacity of these contracts is 787 MW. The capacity contracts extend through 2026 and obligate both CL&P and UI to make or receive payments on a monthly basis to or from the generation facilities based on the difference between a set capacity price and the capacity market price received in the ISO-NE capacity markets. In addition, CL&P has a contract to purchase 0.1 million MWh of energy per year through 2020. NSTAR Electric has a renewable energy contract to purchase 0.1 million MWh of energy per year through 2018 and a capacity - related contract to purchase up to 35 MW per year through 2019. As of June 30, 2015 and December 31, 2014 , Eversource had NYMEX financial contracts for natural gas futures in order to reduce variability associated with the purchase price of approximately 6.8 million and 8.8 million MMBtu of natural gas, respectively. For the three months ended June 30 , 2015 and 2014, there were losses of $ 36.6 million and gains of $ 111.6 million , respectively, recorded as regulatory assets and liabilities, which reflect the current change in fair va lue associated with Eversource's derivative contracts . For the six months ended June 30, 2015 and 2014 , t here were losses of $ 50.1 million and gains of $166 million, respectively. Credit Risk Certain of Eversource ' s derivative contracts contain credit risk contingent provisions . These provisions require Eversource to maintain investment grade credit ratings from the major rating agencies and to post collateral for contracts in a net liability position over specified credit limits. As of June 30 , 2015 and December 31, 201 4 , Eversource had approximately $ 1.3 million and $ 10 million, respectively, of derivative contracts in a net liability position that were subject to credit risk c ontingent provisions and would have been required to post additional collateral of approximately $ 1.3 million and $ 10 million, respectively, if E versource parent ' s unsecured debt credit ratings had been downgraded to below investment grade. Fair Value Measurements of Derivative Instruments Derivative contracts classified as Level 2 in the fair value hierarchy relate to the financial contracts for natural gas futures. Prices are obtained from broker quotes and are based on actual market activity. The contracts are valued using NYMEX natural gas prices . Valuations of these contracts also incorporate discount rates using the yield curve approach. The fair value of derivative contracts classified as Level 3 utilizes significant unobservable inputs. The fair value is modeled using income techniques, such as discounted cash flow valuations adjusted for assumptions relating to exit price. Significant observable inputs for valuations of these contracts include energy and energy-related product prices in future years for which quoted prices in an active market exist. Fair value measurements categorized in Level 3 of the fair value hierarchy are prepared by individuals with expertise in valuation techniques, pricing of energy and energy-related products, and accounting requirements. The future power and capacity prices for periods that are not quoted in an active market or established at auction are based on available market data and are escalated based on estimates of inflation to address the full time period of the contract. Valuations of derivative contracts using a discounted cash flow methodology include assumptions regarding the timing and likelihood of scheduled payments and also reflect non-performance risk, including credit, using the default probability approach based on the counterparty ' s credit rating for assets and the Company ' s credit rating for liabilities. Valuations incorporate estimates of premiums or discounts that would be required by a market participant to arrive at an exit price, using historical market transactions adjusted for the terms of the contract. The following is a summary of Eversource 's, including CL&P's and NSTAR Electric's, Level 3 derivative contracts and the range of the significant unobservable inputs utilized in the valuations over the duration of the contracts : As of June 30, 2015 As of December 31, 2014 Range Period Covered Range Period Covered Energy Prices: Eversource, CL&P $ 45 per MWh 2020 $ 52 per MWh 2020 Capacity Prices: Eversource $ 10.05 - 12.60 per kW-Month 2016 - 2026 $ 5.30 - 12.98 per kW-Month 2016 - 2026 CL&P $ 10.81 - 12.60 per kW-Month 2019 - 2026 $ 11.08 - 12.98 per kW-Month 2018 - 2026 NSTAR Electric $ 10.05 - 10.81 per kW-Month 2016 - 2019 $ 5.30 - 11.10 per kW-Month 2016 - 2019 Forward Reserve: Eversource, CL&P $ 2.40 per kW-Month 2015 - 2024 $ 5.80 - 9.50 per kW-Month 2015 - 2024 REC Prices: Eversource, NSTAR Electric $ 46 - 51 per REC 2015 - 2018 $ 38 - 56 per REC 2015 - 2018 Exit price premiums of 6 percent through 23 percent are also applied on these contracts and reflect the most recent market activity available for similar type contracts . Significant increases or decreases in future energy or capacity prices in isolation would decrease or increase, respectively, the fair value of the derivative liability. Any increases in the risk premiums would increase the fair value of the derivative liabilities. Changes in these fair values are recorded as a regulatory asset or liability and would not impact net income. Valuations using significant unobservable inputs: The following table present s changes in the Level 3 category of derivative assets and derivative liabilities measured at fair value on a recurring basis. The derivative assets and liabilities are presented on a net basis. For the Three Months Ended June 30, 2015 2014 NSTAR NSTAR (Millions of Dollars) Eversource CL&P Electric Eversource CL&P Electric Derivatives, Net: Fair Value as of Beginning of Period $ (406.8) $ (403.3) $ (3.5) $ (564.3) $ (557.0) $ (7.3) Net Realized/Unrealized Gains/(Losses) Included in Regulatory Assets and Liabilities (37.1) (36.8) (0.3) 111.8 112.2 (0.4) Settlements 21.5 19.9 1.6 21.6 20.2 1.4 Fair Value as of End of Period $ (422.4) $ (420.2) $ (2.2) $ (430.9) $ (424.6) $ (6.3) For the Six Months Ended June 30, 2015 2014 NSTAR NSTAR (Millions of Dollars) Eversource CL&P Electric Eversource CL&P Electric Derivatives, Net: Fair Value as of Beginning of Period $ (415.4) $ (410.9) $ (4.5) $ (635.2) $ (630.6) $ (7.3) Net Realized/Unrealized Gains/(Losses) Included in Regulatory Assets and Liabilities (49.2) (48.9) (0.3) 161.3 164.5 (0.5) Settlements 42.2 39.6 2.6 43.0 41.5 1.5 Fair Value as of End of Period $ (422.4) $ (420.2) $ (2.2) $ (430.9) $ (424.6) $ (6.3)

MARKETABLE SECURITIES

MARKETABLE SECURITIES	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Marketable Securities [Text Block]	5. MARKETABLE SECURITIES Eversource maintains trusts to fund certain non-qualified executive benefits and WMECO maintains a spent n uclear fuel trust to fund WMECO' s prior peri od spent nuclear fuel liability. These trusts hold marketable securities. These trusts are not subject to regulatory oversight by state or federal agencies. In addition, CYAPC and YAEC maintain legally restricted trusts, each of which holds marketable securities, for paying the decommissioning and fuel removal obligations of their nuclear fuel storage facilities . Trading Securities: T he Company elected to record certain equity securities a s trading securities, with the changes in fair values recorded in Other Income, Net on the statements of income. As of June 30 , 2015 and December 31, 2014 , these securities were classified as Leve l 1 in the fair value hierarchy and totaled $ 14.9 million and $85.1 million, respectively . N et gains on these securities of $ 0. 5 million and $ 3.1 million for the three months ended June 30, 2015 and 2014 , respectively, and net gains of $ 2 .1 million and $ 3.8 million, respectively , for the six months ended June 30, 2015 and 2014, respectively , were recorded in Other Income, Net on the statements of income. Dividend income is recorded in Other Income, Net when dividends are declared. During the second quarter of 2015, certain of the securities classified as trading securities were sold and the proceeds were re-invested in equity securities designated as available-for-sale securities. Available-for-Sale Securities: The following is a summary of E versource ' s and WMECO' s available-for-sale securities. These securities are recorded at fair value and are included in current and long-term Marketable Securities on the balance sheets. As of June 30, 2015 As of December 31, 2014 Pre-Tax Pre-Tax Pre-Tax Pre-Tax Amortized Unrealized Unrealized Amortized Unrealized Unrealized (Millions of Dollars) Cost Gains Losses Fair Value Cost Gains Losses Fair Value Eversource Debt Securities (1) $ 315.3 $ 4.9 $ (0.6) $ 319.6 $ 313.0 $ 7.5 $ (0.3) $ 320.2 Equity Securities (1) 216.5 72.9 (1.2) 288.2 160.6 73.3 - 233.9 WMECO Debt Securities (2) 58.3 - - 58.3 58.2 - (0.1) 58.1 Eversource 's amounts include CYAPC's and YAEC's marketable securities held in nuclear decommissioning trusts of $ 450 million and $450.8 million as of June 30 , 2015 and December 31, 2014, respectively, which are legally restricted and can only be used for the costs of decommissioning and fuel removal of the nuclear fuel storage facilities owned by these companies. Unrealized gains and losses for the nuclear decommissioning trusts are recorded in Marketable Securities with the corresponding offset to Other Long-Term Liabilities on the balance sheets, with no impact on the statements of income. Unrealized gains and losses on debt securities held by WMECO are recorded in Marketable Securities with the corresponding offset to Other Long-Term Assets on the balance sheets. Unrealized Losses and Other-than-Temporary Impairment: There have been no significant unrealized losses, other-than-temporary imp airments or credit losses for Eversource or WMECO. Factors considered in determining whether a credit loss exists include the duration and severity of the impairment, adverse conditions specifically affecting the issuer, and the payment history, ratings and rating changes of the security. For asset-backed debt securities, underlying collateral and expected future cash flows are also evaluated. Realized Gains and Losses: Realized gains and losses on available-for-sale securities are reco rded in Other Income, Net for Eversource 's benefit trust, Other Long-Term Assets for WMECO, and are offset in Other Long-Term Liabilities for CYAPC and YAEC. Eversource utilizes the specific ident ification basis method for the Eversource benefit trust , and the average cost basis method for the WMECO trust and the CYAPC and YAEC nuclear decommissioning trusts to compute the realized gains and losses on the sale of available-for-sale securities. Contractual Maturities : As of June 30 , 2015, the contractual maturities of available-for-sale debt securities were as follows: Eversource WMECO Amortized Amortized (Millions of Dollars) Cost Fair Value Cost Fair Value Less than one year (1) $ 66.1 $ 66.1 $ 38.4 $ 38.4 One to five years 70.4 70.8 16.2 16.2 Six to ten years 60.1 61.2 0.6 0.6 Greater than ten years 118.7 121.5 3.1 3.1 Total Debt Securities $ 315.3 $ 319.6 $ 58.3 $ 58.3 1) Amou nts in the Less than one year E versource category include securities in the CYAPC and YAEC nuclear decommissioning trusts, which are restricted and are classified in long-term Marketable Securities on the balance sheets. Fair Value Measurements: The following table presents the marketable securities recorded at fair value on a recurring basis by the level in which they are classified within the fair value hierarchy: Eversource WMECO (Millions of Dollars) As of June 30, 2015 As of December 31, 2014 As of June 30, 2015 As of December 31, 2014 Level 1: Mutual Funds and Equities $ 303.1 $ 319.0 $ - $ - Money Market Funds 26.4 24.9 2.1 4.3 Total Level 1 $ 329.5 $ 343.9 $ 2.1 $ 4.3 Level 2: U.S. Government Issued Debt Securities (Agency and Treasury) $ 38.6 $ 51.3 $ - $ - Corporate Debt Securities 60.1 49.1 13.6 14.7 Asset-Backed Debt Securities 32.0 54.1 10.0 14.5 Municipal Bonds 126.9 116.3 10.8 13.0 Other Fixed Income Securities 35.6 24.5 21.8 11.6 Total Level 2 $ 293.2 $ 295.3 $ 56.2 $ 53.8 Total Marketable Securities $ 622.7 $ 639.2 $ 58.3 $ 58.1 U.S. government issued debt securities are valued using market approaches that incorporate transactions for the same or similar bonds and adjustments for yields and maturity dates. Corporate debt securities are valued using a market approach, utilizing recent trades of the same or similar instrument and also incorporating yield curves, credit spreads and specific bond terms and conditions. Asset-backed debt securities include collateralized mortgage obligations, commercial mortgage backed securities, and securities collateralized by auto loans, credit card loans or receivables. Asset-backed debt securities are valued using recent trades of similar instruments, prepayment assumptions, yield curves, issuance and maturity dates, and tranche information. Municipal bonds are valued using a market approach that incorporates reported trades and benchmark yields. Other fixed income securities are valued using pricing models, quoted prices of securities with similar characteristics, and discounted cash flows.

SHORT TERM AND LONG TERM DEBT

SHORT TERM AND LONG TERM DEBT	6 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Debt Disclosure	6. SHORT-TERM AND LONG-TERM DEBT Credit Agreements and Commercial Paper Programs: Eversource parent, CL&P, PSNH, WMECO, NSTAR Gas and Yankee Gas are parties to a five-year $1.45 billion revolving credit facility that expires September 6, 2019 . The facility serves to backstop Eversource parent's $1.45 billion commercial paper program. The commercial paper program allows Eversource parent to issue commercial paper as a form of short-term debt . As of June 30 , 2015 and December 31, 2014 , E versource parent had $ 57 6.5 m illion and approximately $1. 1 billion, respectively, in short-term borrowings outstanding under the Eversource parent commercial paper program, leaving $ 873.5 million and $ 348.9 million of available borrowing capacity as of June 30 , 2015 and December 31, 2014 , respectively. The weighted-average interest rate on these borrowings as of June 30 , 2015 and December 31, 2014 was 0.40 percent and 0.43 percent, r espectively . As of June 30 , 2015 , there were intercompany loans from E versource parent of $ 85.6 million to CL&P, $ 133.5 million to PSNH and $ 60.6 million to WMECO. As of December 31, 2014, there were intercompany loans from E versource parent of $133.4 million to CL&P, $90.5 million to PSNH and $21.4 million to WMECO . NSTAR Electric has a five-year $450 million revolving credit facility that expires September 6, 2019 . The facility serves to bac kstop NSTAR Electric's $450 million commercial paper program. As of June 30 , 2015 and December 31, 2014 , NSTAR Electric had $ 377.2 million and $ 302 million, respectively, in short-term borrowings outstanding under its commercial paper program, leaving $ 72.8 million and $ 148 million of available borrowing capacity as of June 30 , 2015 and December 31, 2014 , respectively. The weighted-average interest rate on these borrowings as of June 30 , 2015 and December 31, 2014 was 0.19 percent and 0.27 percent, respectively . On June 16, 2015, the FERC granted authorization to allow CL&P and WMECO to incur total short-term borrowings up to a maximum of $600 million and $300 million, respectively, effective January 1, 2016 through December 31, 2017. Except as described below, amounts outstanding under the commercial paper programs are included in Notes Payable for Eversource and NSTAR Electric and classified in current liabilities on the balance sheets as all borrowings are outstanding for no more than 364 days at one time. Intercompany loans from E versource parent to CL&P, PSNH and WMECO ar e included in Notes Payable to Eversource Parent and classified in current liabilities on the balance sheets. Intercompany loans from Eversource parent to CL&P, PSNH and WMECO are eliminated in consolidation in Eversource 's balance sheets. Long-Term Debt: On January 15, 2015, Eversource parent issued $150 million of 1.60 percent Series G Senior Notes , due to mature in 2018 and $300 million of 3.15 percent Series H Senior Notes, due to mature in 2025. The proceeds, net of issuance costs, were used to repay short-term borrowings outstanding under the Eversource parent commercial paper program. As the debt issuances refinanced short-term debt, the short-term debt was classified as Long-Term Debt as of December 31, 2014. O n April 1, 2015, CL&P repaid at maturity the $100 million 5.00 percent 2005 Series A First and Refunding Mortgage Bonds using short-term borrowings. On April 1, 2015, CL&P also redeemed the $62 million 199 6 A Series 1.55 percent PCRB s that were subject to mandatory tender , using short term borrowings . On May 20, 2015, CL&P issued $300 million of 4.15 percent 2015 Series A First and Refunding Mortgage Bonds due to mature in 2045. The proceeds, net of issuance costs, were used to repay short-term borrowings. On August 1, 2015, WMECO repaid at maturity the $50 million 5.24 percent Series C Senior Notes using short-term borrowings. Long-Term Debt Issuance Authorization : On April 3 , 2015, the DPU authorized NSTAR Gas to issue up to $100 million in long-term debt for the period through December 31, 2015.

PENSION BENEFITS AND POSTRETIRE

PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSIONS	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Pension and Other Postretirement Benefits Disclosure [Text Block]	7 . Pension Benefits and Postretirement Benefits Other than Pensions As of December 31, 2014, Eversource S ervice sponsored two defined benefit retirement plans that covered eligible employees, including employees of CL&P, NSTAR Electric, PSNH and WMECO . Effective January 1, 2015, the two pension plans were merg ed into one plan, sponsored by E versource S ervice . As of December 31, 2014, Eversource Se rvice also sponsored defined benefit postretirement plans that provide certain retiree benefits, primarily medical, dental and life insurance, to retiring employees that meet certain age and service eligibility requirements , including employees of CL&P, NSTAR Electric, PSNH and WMECO . Effective January 1, 2015, the postretirement plans were merged into one plan, sponsored by E versource S ervice . The components of net periodic benefit expense for the Pension, SERP and PBOP Plans are shown below. The net periodic benefit expense and the intercompany allocations less the capitalized portion of pension , SERP and PBOP amounts is included in Operations and Maintenance on the statements of income. Capitalized pension and PBOP amounts relate to employees working on capital projects and are included in Property, Plant and Equipment, Net. Intercompany allocations are not included in the CL&P, NSTAR Electric, PSNH and WMECO net periodic benefit expense amounts. Pension, SERP and PBOP expense reflected in the statements of cash flows for CL&P, NSTAR Electric, PSNH and WMECO does not include the intercompany allocations and the corresponding capitalized portion, as these amounts are cash settled on a short-term basis. Pension and SERP Pension and SERP Eversource For the Three Months Ended For the Six Months Ended (Millions of Dollars) June 30, 2015 (1) June 30, 2014 June 30, 2015 (1) June 30, 2014 Service Cost $ 22.8 $ 19.1 $ 45.9 $ 41.5 Interest Cost 56.9 56.3 113.3 113.0 Expected Return on Plan Assets (83.9) (77.7) (168.2) (155.4) Actuarial Loss 36.5 31.7 75.5 64.7 Prior Service Cost 0.9 1.1 1.8 2.1 Total Net Periodic Benefit Expense $ 33.2 $ 30.5 $ 68.3 $ 65.9 Capitalized Pension Expense $ 9.8 $ 8.7 $ 21.1 $ 18.4 PBOP PBOP Eversource For the Three Months Ended For the Six Months Ended (Millions of Dollars) June 30, 2015 (1) June 30, 2014 June 30, 2015 (1) June 30, 2014 Service Cost $ 3.9 $ 3.2 $ 8.1 $ 6.3 Interest Cost 11.7 12.1 23.6 24.7 Expected Return on Plan Assets (16.9) (15.8) (33.7) (31.6) Actuarial Loss 1.7 3.0 3.4 6.0 Prior Service Credit (0.2) (0.7) (0.2) (1.4) Total Net Periodic Benefit Expense $ 0.2 $ 1.8 $ 1.2 $ 4.0 Capitalized PBOP Expense/(Income) $ (0.1) $ 0.4 $ - $ 0.8 Pension and SERP For the Three Months Ended June 30, 2015 For the Three Months Ended June 30, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH (1) WMECO CL&P Electric PSNH WMECO Service Cost $ 6.2 $ 3.7 $ 3.1 $ 1.0 $ 5.0 $ 3.0 $ 2.3 $ 0.8 Interest Cost 12.9 10.0 6.1 2.6 12.4 10.3 5.8 2.5 Expected Return on Plan Assets (19.8) (17.5) (10.1) (4.7) (18.7) (15.7) (9.3) (4.4) Actuarial Loss 8.0 8.7 2.9 1.6 8.2 5.9 2.8 1.7 Prior Service Cost 0.4 - 0.1 0.1 0.5 - 0.1 0.1 Total Net Periodic Benefit Expense $ 7.7 $ 4.9 $ 2.1 $ 0.6 $ 7.4 $ 3.5 $ 1.7 $ 0.7 Intercompany Allocations $ 5.8 $ 3.4 $ 1.6 $ 1.1 $ 7.5 $ 1.4 $ 2.1 $ 1.4 Capitalized Pension Expense $ 4.7 $ 2.7 $ 0.9 $ 0.5 $ 4.4 $ 1.0 $ 0.8 $ 0.6 Pension and SERP For the Six Months Ended June 30, 2015 For the Six Months Ended June 30, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH (1) WMECO CL&P Electric PSNH WMECO Service Cost $ 12.2 $ 7.5 $ 6.0 $ 2.2 $ 10.2 $ 7.6 $ 5.1 $ 1.9 Interest Cost 25.4 20.1 12.1 5.2 25.7 20.6 12.3 5.2 Expected Return on Plan Assets (39.4) (35.1) (20.2) (9.4) (38.0) (31.5) (19.5) (9.0) Actuarial Loss 16.2 18.4 5.8 3.2 17.3 11.7 6.0 3.5 Prior Service Cost 0.8 - 0.2 0.1 0.9 - 0.3 0.2 Total Net Periodic Benefit Expense $ 15.2 $ 10.9 $ 3.9 $ 1.3 $ 16.1 $ 8.4 $ 4.2 $ 1.8 Intercompany Allocations $ 12.2 $ 6.9 $ 3.4 $ 2.3 $ 14.3 $ 3.8 $ 4.2 $ 2.7 Capitalized Pension Expense $ 9.4 $ 5.9 $ 1.7 $ 1.0 $ 9.3 $ 2.9 $ 1.7 $ 1.4 PBOP For the Three Months Ended June 30, 2015 For the Three Months Ended June 30, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH (1) WMECO CL&P Electric PSNH WMECO Service Cost $ 0.5 $ 1.3 $ 0.3 $ 0.1 $ 0.5 $ 0.8 $ 0.3 $ 0.1 Interest Cost 1.8 4.7 1.0 0.3 1.9 4.8 1.0 0.4 Expected Return on Plan Assets (2.8) (6.9) (1.5) (0.6) (2.5) (6.5) (1.3) (0.6) Actuarial Loss/(Gain) 0.2 0.4 0.1 - 1.0 (0.2) 0.6 0.1 Prior Service Credit - (0.1) - - - (0.5) - - Total Net Periodic Benefit Expense/(Income) $ (0.3) $ (0.6) $ (0.1) $ (0.2) $ 0.9 $ (1.6) $ 0.6 $ - Intercompany Allocations $ 0.4 $ 0.2 $ 0.1 $ 0.1 $ 1.1 $ - $ 0.3 $ 0.2 Capitalized PBOP Expense/(Income) $ (0.1) $ (0.2) $ - $ - $ 0.5 $ (0.5) $ 0.2 $ - PBOP For the Six Months Ended June 30, 2015 For the Six Months Ended June 30, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH (1) WMECO CL&P Electric PSNH WMECO Service Cost $ 1.1 $ 2.7 $ 0.7 $ 0.2 $ 1.1 $ 1.6 $ 0.7 $ 0.2 Interest Cost 3.5 9.5 1.9 0.8 4.0 9.7 2.1 0.8 Expected Return on Plan Assets (5.5) (13.7) (3.0) (1.3) (5.2) (13.0) (2.7) (1.1) Actuarial Loss/(Gain) 0.3 1.2 0.3 - 2.1 (0.3) 1.1 0.2 Prior Service Credit - (0.1) - - - (0.9) - - Total Net Periodic Benefit Expense/(Income) $ (0.6) $ (0.4) $ (0.1) $ (0.3) $ 2.0 $ (2.9) $ 1.2 $ 0.1 Intercompany Allocations $ 0.9 $ 0.4 $ 0.2 $ 0.2 $ 2.2 $ 0.1 $ 0.6 $ 0.4 Capitalized PBOP Expense/(Income) $ (0.1) $ (0.1) $ 0.1 $ (0.1) $ 1.0 $ (1.0) $ 0.4 $ 0.1 (1) Amounts exclude approximately $0.8 million and $1.6 million for the three and six months ended June 30, 2015, respectively, that represented amounts included in other deferred debits.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Commitments and Contingencies Disclosure [Text Block]	8 . COMMITMENTS AND CONTINGENCIES A. Environmental Matters General: E versource , CL&P, NSTAR Electric, PSNH and WMECO are subject to environmental laws and regulations intended to mitigate or remove the effect of past operations and improve or maintain the quality of the environment. These laws and regulations require the removal or the remedy of the effect on the environment of the disposal or release of certain specified hazardous substances at current and former operating sites. E versource , CL&P, NSTAR Electric , PSNH and WMECO have an active environmental auditing and training program and believe that they are substantially in compliance with all enacted laws and regulations. The number of environmental sites and reserves related to these sites for which remediation or long-term monitoring, preliminary site work or site assessment are being performed are as follows : As of June 30, 2015 As of December 31, 2014 Reserve Reserve Number of Sites (in millions) Number of Sites (in millions) Eversource 65 $ 46.2 65 $ 43.3 CL&P 15 4.9 16 3.8 NSTAR Electric 14 2.3 13 1.1 PSNH 12 3.4 13 5.2 WMECO 4 0.6 4 0.5 Included in the Eversource number of sites and reserve amounts above are former MGP sites that were operated several decades ago and manufactured gas from coal and other processes, which resulted in certain by-products remaining in the environment that may pose a potential risk to human health and the environment. The reserve balance related to these former MGP sites was $ 40 mi llion and $ 38.8 million as of June 30 , 2015 and December 31, 201 4 , respectively, and relates primarily to the natural gas business segment. These estimates are subjective in nature as they take into consideration several different remediation options at each specific site. The reliability and precision of these estimates can be affected by several factors, including new information concerning either the level of contamination at the site, the extent of Eversource, CL&P, NSTAR Electric, PSNH, or WMECO's responsibility or the extent of remediation required, recently enacted laws and regulations or a change in the estimates due to certain economic factors. B . Guarantees and Indemnifications E versource parent provides credit assurances on behalf of its subsidiaries, including CL&P, NSTAR Electric, PSNH and WMECO, in the form of guarantees in the normal course of business. E versource parent also issued a guaranty on behalf of its subsidiary, NPT, under which, beginning at the time the Northern Pass Transmission line goes into commercial operation, E versource parent will guarantee the financial obligations of NPT under the TSA in an amount not to exceed $25 million. E versource parent 's obligations under the guaranty expire upon the full, final and indefeasible payment of the guaranteed obligations. Eversource p arent has provided a guar anty of various indemnification and other obligations as a result of the April 13 , 2015 sale of substantially all of the assets of E.S. Boulos Company, an unregulated electrical contractor based in Maine and indirect subsidiary of Eversource Energy . E versource parent has also guarantee d certain indemnification and other obligations as a result of the sale s of former unregulated subsidiar ies and the termination of an unregulated business , with maximum exposure s either not specified or not material. Management does not a ntic ipate a material impact to Net Income as a result of these various guarantees and indemnifications. T he following table summarizes E versource parent 's guarantees of its subsidiaries, including CL&P, NSTAR Electric, PSNH and WMECO, Maximum Exposure Company Description (in millions) Expiration Dates On behalf of subsidiaries: Various Surety Bonds (1) $ 33.8 2015 - 2016 Eversource Service and Rocky River Realty Company Lease Payments for Vehicles and Real Estate $ 12.7 2019 and 2024 On behalf of external parties: Purchaser of E.S. Boulos Company and a bonding company E.S. Boulos Company Indemnification $ 42.1 2016 and 2020 (1) Surety bo nd expiration dates reflect termination dates, the majority of which will be renewed or extended. C ertain surety bonds contain credit rating s triggers that would require Eversource parent to post collateral in the event that the unsecured debt credit ratings of Eversource are downgraded . C . FERC ROE Complaints T hree separate complaints have been filed at FERC by combinations of New England state attorneys general, state regulatory commissions, consumer advocates, consumer groups, municipal parties and other parties (the "Complainants"). In the first complaint, filed in 2011, the Complainants alleged that the NETOs' base ROE of 11.14 percent that had been utilized since 2006 was unjust and unreasonable, asserted that the rate was excessive due to changes in the capital markets, and sought an order to reduce it prospectively from the date of the final FERC order and for the 15-month period beginning October 1, 2011 to December 31, 2012 (the "first complaint refund period"). In the second and third complaints, filed in 2012 and 2014, the Complainants challenged the NETOs' base ROE and sought refunds for the 15-month periods beginning December 27, 2012 and July 31, 2014. In 2014, the FERC determined that the base ROE should be set at 10.57 percent for the first complaint refund period and that a utility's total or maximum ROE should not exceed the top of the new zone of reasonableness, which was set at 11.74 percent. The FERC ordered the NETOs to provide refunds to customers for the first complaint refund period and set the new base ROE of 10.57 percent prospectively from October 16, 2014. The NETOs and the Complainants sought rehearing from FERC. In late 2014, the NETOs made a compliance filing, which was challenged by the Complainants, and the Company began refunding amounts from the first complaint period. On March 3, 2015, FERC issued an order denying all issues raised on rehearing by the NETOs and Co mplainants in the first complaint. The FERC order upheld the base ROE of 10.57 percent for the first complaint refund period and prospectively from October 16, 2014, and upheld that the utility's total ROE (the base ROE plus any incentive adders) for the transmission assets to which the adder applies is capped at the top of the zone of reasonableness, which is currently set at 11.74 percent . As a result of the clarifying information in the March 2015 order related to the application of the ROE cap, Eversource adjusted its reserve in the first half of 2015 and recognized a pre-tax charge to earnings (excluding interest) of $ 20 million, of which $ 12.5 million was recorded at CL&P, $ 2.4 million at NSTAR Electric, $ 1 million at PSNH, and $ 4.1 million at WMECO. The pre-tax charge was recorded as a regulatory liability and as a reduction to Operating Revenues. The NETOs and Complainants have filed appeals to the D.C. Circuit Court of Appeals, which have been consolidated, and no schedule has been set. For the second and third complaint proceedings, hearings were held in late June and early July 2015 before a FERC ALJ and initial briefs were filed on July 29, 2015. The state parties, municipal utilities and FERC trial staff each believe that the base ROE should be reduced . T he NETOs believe that the Complainants' positions are without merit, and the existing ROEs should be maintained. The FERC ALJ's initial decision is expected by December 30, 2015, and a final FERC order is expected in the third quarter of 2016. D . Basic Service Bad Debt Adder On January 7, 2015, the DPU issued an order concluding that NSTAR Electric had removed energy-related bad debt costs from base distribution rates effective January 1, 2006. The DPU ordered NSTAR Electric and the Massachusetts Attorney General to collaborate on the reconciliations of energy-related bad debt costs through 2014. As a result of the DPU order, NSTAR Electric increased its regulatory assets and reduced operations and maintenance expense by $24.2 million in the first quarter, resulting in after-tax earnings of $14.5 million. On May 5, 2015, NSTAR Electric filed for recovery of the energy-related bad debt costs regulatory asset from customers beginning July 1, 2015. On June 24, 2015, the DPU delayed the effective date of NSTAR Electric's proposed rate increase from July 1, 2015 to November 1, 2015 to allow for the DPU staff to review the reconciliations. The established procedural schedule is expected to result in an approval of the proposed rate increase in the fourth quarter of 2015. E . PSNH Generation Restructuring On June 10, 2015, Eversource and PSNH entered into the 2015 Public Service Company of New Hampshire Restructuring and Rate Stabilization Agreement (the Agreement) with the New Hampshire Office of Energy and Planning, certain members of the Staff of the NHPUC, the Office of Consumer Advocate, two State Senators, and several other parties. The Agreement was filed with the NHPUC on the same day. Under the terms of the Agreement, PSNH has agreed to pursue the divestiture of its generation assets upon NHPUC approval. The Agreement is designed to provide a resolution of issues pertaining to PSNH's generation assets in pending regulatory proceedings before the NHPUC. When implemented, the Agreement provides for the Clean Air Project prudence proceeding to be resolved and all remaining Clean Air Project costs to be included in rates effective January 1, 2016. As part of the Agreement, PSNH has agreed to forego recovery of $25 million of the deferred equity return related to the Clean Air Project. In addition, PSNH will not seek a general distribution rate increase effective before July 1, 2017 and will contribute $5 million to create a clean energy fund, which will not be recoverable from its customers. In the second quarter of 2015, PSNH recorded the $5 million contribution as a long-term liability and an increase to Operations and Maintenance expense on the statements of income. Upon completion of the divestiture process, all remaining stranded costs, including any remaining deferred equity return in excess of the $25 million that PSNH has agreed to forego, will be recovered via bonds that will be secured by a non- bypassable charge in rates billed to PSNH's customers. Implementation of the Agreement is subject to NHPUC approval, which is expected in late 2015.

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Fair Value Disclosures [Text Block]	9 . FAIR VALUE OF FINANCIAL INSTRUMENTS The following methods and assumptions were used to estimate the fair value of each of the following financial instruments: Preferred Stock and Long-Term Debt: The fair value of CL& P's and NSTAR Electric' s preferred stock is based upon pricing models that incorporate interest rates and other market factors, valuations or trades of similar securities and cash flow project ions. The fair value of long-term debt securities is based upon pricing models that incorporate quoted market prices for those issues or similar issues adjusted for market conditions, credit ratings of the respective companies and treasury benchmark yields. The fair values provided in the tables below are classified as Level 2 within the fair value hierarchy . Carrying amounts and estimated fair values are as follows : As of June 30, 2015 As of December 31, 2014 Eversource Carrying Fair Carrying Fair (Millions of Dollars) Amount Value Amount Value Preferred Stock Not Subject to Mandatory Redemption $ 155.6 $ 154.8 $ 155.6 $ 153.6 Long-Term Debt 8,968.5 9,329.9 8,851.6 9,451.2 As of June 30, 2015 CL&P NSTAR Electric PSNH WMECO Carrying Fair Carrying Fair Carrying Fair Carrying Fair (Millions of Dollars) Amount Value Amount Value Amount Value Amount Value Preferred Stock Not Subject to Mandatory Redemption $ 116.2 $ 113.0 $ 43.0 $ 41.8 $ - $ - $ - $ - Long-Term Debt 2,975.1 3,242.9 1,792.7 1,916.6 1,076.3 1,133.0 628.0 658.0 As of December 31, 2014 CL&P NSTAR Electric PSNH WMECO Carrying Fair Carrying Fair Carrying Fair Carrying Fair (Millions of Dollars) Amount Value Amount Value Amount Value Amount Value Preferred Stock Not Subject to Mandatory Redemption $ 116.2 $ 112.0 $ 43.0 $ 41.6 $ - $ - $ - $ - Long-Term Debt 2,842.0 3,214.5 1,797.4 1,993.5 1,076.3 1,137.9 628.5 689.4 Derivative Instruments: D erivative instruments are carried at fair value. For further information, see Note 4 , "Derivative Instruments," to the financial statements. Other Financial Instruments: Investments in marketable secur ities are carried at fair value. For further information, see Note 5 , "Marketable Securities," to the financial statements. The carrying value of other financial instruments included in current assets and current liabilities, including cash and cash equivalents and special deposits, approximates their fair value due to the short-term nature of these instruments . See Note 1D, "Summary of Significant Accounting Policies - Fair Value Measurements," for the fair value measurement policy and the fair value hierarchy .

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE INCOME	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Comprehensive Income Note [Text Block]	10. ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) The change s in accumulated other comprehensive income /( loss) by component , net of tax, is as follows : For the Six Months Ended June 30, 2015 For the Six Months Ended June 30, 2014 Qualified Unrealized Qualified Unrealized Cash Flow Gains/(Losses) Defined Cash Flow Gains on Defined Eversource Hedging on Marketable Benefit Hedging Marketable Benefit (Millions of Dollars) Instruments Securities Plans Total Instruments Securities Plans Total Balance as of Beginning of Period $ (12.4) $ 0.7 $ (62.3) $ (74.0) $ (14.4) $ 0.4 $ (32.0) $ (46.0) OCI Before Reclassifications - (1.1) (0.4) (1.5) - 0.5 1.2 1.7 Amounts Reclassified from AOCI 1.0 - 2.5 3.5 1.0 - 1.8 2.8 Net OCI 1.0 (1.1) 2.1 2.0 1.0 0.5 3.0 4.5 Balance as of End of Period $ (11.4) $ (0.4) $ (60.2) $ (72.0) $ (13.4) $ 0.9 $ (29.0) $ (41.5) E versource 's qualified cash flow hedging instruments represent interest rate swap agreements on debt issuances that were settled in prior years. The settlement amount was recorded in AOCI and is being amortized into Net Income over the term of the underlying debt instrument. CL&P, PSNH and WMECO continue to amortize interest rate swaps settled in prior years from AOCI into Interest Expense over the remaining life of the associated long-term debt, which are not material to their respective financial statements. The amortization expense of actuarial gains and losses on the defined benefit plans is amortized from AOCI into Operations and Maintenance over the average future employee s ervice period, and is reflected in amounts reclassified from AOCI. The related tax effects of the reclassification adjustments are not material to the financial statements for the six months ended June 30 , 2015 and 2014.

COMMON SHARES

COMMON SHARES	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule of Stock by Class [Text Block]	11 . COMMON SHARES The following table sets fo rth the E ve r s ource parent common shares and the shares of common stock of CL&P, NSTAR Electric , PSNH and WMECO that were authorized and issued and the respective per share par values : Shares Authorized as of Per Share June 30, 2015 and Issued as of Par Value December 31, 2014 June 30, 2015 December 31, 2014 Eversource $ 5 380,000,000 333,833,308 333,359,172 CL&P $ 10 24,500,000 6,035,205 6,035,205 NSTAR Electric $ 1 100,000,000 100 100 PSNH $ 1 100,000,000 301 301 WMECO $ 25 1,072,471 434,653 434,653 As of June 30 , 2015 and December 31, 2014 , there were 16,671,366 and 16,375,835 E versource common shares held as treasury shares, respectively. As of June 30 , 2015 and December 31, 2014 , Eversource common sha res outstanding were 317,161,942 and 316 , 983 , 337 , respectively. In May 2015, the Company repurchased 532,521 treasury shares at a share price of $47.94.

COMMON SHARESHOLDERS' EQUITY AN

COMMON SHARESHOLDERS' EQUITY AND NONCONTROLLING INTERESTS (NU)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Stockholders' Equity Note Disclosure [Text Block]	12 . COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS D ividends on the preferred stock of CL&P and NSTAR Electric totaled $1.9 million f or the three months ended June 30 , 2015 and 2014 and $3.8 million for the six months ended June 30, 2015 and 2014. These dividends w ere presented as Net Income Attributable to Noncontrolling Interests on the Eversource statements of income. Common Shareholders' Equity was fully attributable to the parent and Noncontrolling Interest – Preferred Stock of Subsidiaries was fully attributable to the noncontrolling interest on the Eversource balance sheets.

EARNINGS PER SHARE

EARNINGS PER SHARE	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Earnings Per Share [Text Block]	13 . EARNINGS PER SHARE Basic EPS is computed based upon the weighted average number of common shares outstanding during each period. Diluted EPS is compu ted on the basis of the weighted average number of common shares outstanding plus the potential dilut ive effect of certain share-based compensation awards as if they were converted into common shares . For the three and six months ended June 30 , 2015 and 2014, t here were no antidilutive share awards excluded from the computation . The following table sets forth the components of basic and diluted EPS: Eversource For the Three Months Ended For the Six Months Ended (Millions of Dollars, except share information) June 30, 2015 June 30, 2014 June 30, 2015 June 30, 2014 Net Income Attributable to Controlling Interest $ 207.5 $ 127.4 $ 460.8 $ 363.3 Weighted Average Common Shares Outstanding: Basic 317,613,166 315,950,510 317,352,004 315,742,511 Dilutive Effect 946,402 1,162,291 1,173,374 1,259,950 Diluted 318,559,568 317,112,801 318,525,378 317,002,461 Basic and Diluted EPS $ 0.65 $ 0.40 $ 1.45 $ 1.15 RSUs and performance shares are included in basic weighted average common shares outstanding as of the date that all necessary vesting conditions have been satisfied. The dilutive effect of unvested RSUs and performance shares is calculated using the treasury stock method. Assumed proceeds of the se units under the treasury stock method consist of the remaining compensation cost to be recognized and a theoretical tax benefit. The theoretical tax benefit is calculated as the tax impact of the intrinsic value of the units (the difference between the market value of the average units outstanding for the period, using the average market price during the period, and the grant date market value). The dilutive effect of stock options to purchase common shares is also calculated using the treasury stock method. Assumed proceeds for stock options consist of cash proceeds that would be received upon exercise, and a theoretical tax benefit. The theoretical tax benefit is calculated as the tax impact of the intrinsic value of the stock options (the difference between the market value of the average stock options outstanding for the period, using the average market price during the period, and the exercise price).

SEGMENT INFORMATION

SEGMENT INFORMATION	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Segment Reporting Disclosure [Text Block]	14 . SEGMENT INFORMATION Presentation: Eversource is organized between the Electric Distribution, Electric Transmission and Natural Gas Distribution reportable segments and Other based on a combination of factors, including the characteristics of each segments ' products and services, the sources of operating revenues and expenses and the regulatory environment i n which each segment operates. These reportable segments rep resent substantially all of Eversource 's total consolidated revenues. Revenues from the sale of electricity and natural gas primarily are derived from residential, commercial and industrial customers and are not dependent on any single customer. The Electric Distribution reportable segment includes the generation activities of PSNH and WMECO. The remainder of Eversource ' s operations is presented as Other in the tables below and primarily consists of 1) the equity in earnings of E versource parent from its subsidiaries and intercompany interest income, both of which are eliminated in consolidation, and interest e xpense related to the debt of Eversource parent, 2) the revenues and ex penses of Eversource Service , most of which are eliminated in consolidation, 3) the operations of CYAPC and YAEC, and 4 ) the results of other un regulated subsidiaries, which are not part of its core business. Cash flows used for investments in plant included in the segment information below are cash capital expenditures that do not include amounts incurred but not paid, cost of removal, AFU DC related to equity funds, and the capitalized portions of pension e xpense. Eversource 's reportable segments are determined based upon the level at which Eversource 's chief operating decision maker assesses performance and makes decisions about the allocation o f company resources. Each of Eversource 's subsidiaries, including CL&P, NSTAR Electric, PSNH and WMECO, has one reportable segment. Eversource 's operating segments and reporting units are consistent with its reportable business segments . Eversource 's segment information is as follows : For the Three Months Ended June 30, 2015 Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total Operating Revenues $ 1,382.7 $ 186.0 $ 267.8 $ 203.7 $ (223.1) $ 1,817.1 Depreciation and Amortization (98.5) (17.7) (39.7) (7.1) 0.5 (162.5) Other Operating Expenses (1,052.1) (150.2) (73.1) (190.7) 223.5 (1,242.6) Operating Income 232.1 18.1 155.0 5.9 0.9 412.0 Interest Expense (45.6) (9.1) (26.3) (12.4) 1.1 (92.3) Other Income, Net 5.5 0.3 5.1 220.1 (218.1) 12.9 Net Income Attributable to Controlling Interest $ 120.9 $ 5.3 $ 80.4 $ 217.0 $ (216.1) $ 207.5 For the Six Months Ended June 30, 2015 Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total Operating Revenues $ 3,142.8 $ 693.4 $ 516.8 $ 443.7 $ (466.2) $ 4,330.5 Depreciation and Amortization (257.6) (35.9) (80.1) (14.3) 1.0 (386.9) Other Operating Expenses (2,395.0) (538.7) (147.2) (419.9) 466.7 (3,034.1) Operating Income 490.2 118.8 289.5 9.5 1.5 909.5 Interest Expense (93.2) (18.1) (53.9) (24.1) 2.2 (187.1) Other Income, Net 7.6 0.1 8.1 535.0 (532.2) 18.6 Net Income Attributable to Controlling Interest $ 251.4 $ 61.0 $ 147.0 $ 529.9 $ (528.5) $ 460.8 Cash Flows Used for Investments in Plant $ 319.8 $ 67.5 $ 328.7 $ 24.4 $ - $ 740.4 For the Three Months Ended June 30, 2014 Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total Operating Revenues $ 1,261.8 $ 195.5 $ 206.9 $ 184.7 $ (171.3) $ 1,677.6 Depreciation and Amortization (89.3) (16.9) (37.0) (7.7) 2.3 (148.6) Other Operating Expenses (991.5) (166.5) (71.0) (174.9) 168.9 (1,235.0) Operating Income 181.0 12.1 98.9 2.1 (0.1) 294.0 Interest Expense (47.2) (8.7) (28.8) (9.1) 1.3 (92.5) Other Income, Net 2.9 - 2.7 137.7 (137.8) 5.5 Net Income Attributable to Controlling Interest $ 83.4 $ 2.0 $ 43.9 $ 133.3 $ (135.2) $ 127.4 For the Six Months Ended June 30, 2014 Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total Operating Revenues $ 2,847.8 $ 628.3 $ 458.9 $ 356.9 $ (323.7) $ 3,968.2 Depreciation and Amortization (238.2) (34.6) (74.0) (14.7) 4.1 (357.4) Other Operating Expenses (2,202.4) (487.9) (137.3) (340.3) 318.8 (2,849.1) Operating Income 407.2 105.8 247.6 1.9 (0.8) 761.7 Interest Expense (94.6) (17.1) (54.3) (18.7) 2.2 (182.5) Other Income, Net 4.3 0.1 4.2 432.4 (433.8) 7.2 Net Income Attributable to Controlling Interest $ 195.6 $ 54.1 $ 118.8 $ 424.9 $ (430.1) $ 363.3 Cash Flows Used for Investments in Plant $ 335.6 $ 68.6 $ 289.3 $ 30.5 $ - $ 724.0 The following table summarizes Eversource's segmented total assets: Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total As of June 30, 2015 $ 17,872.9 $ 2,933.4 $ 7,589.7 $ 12,455.7 $ (10,971.8) $ 29,879.9 As of December 31, 2014 17,563.4 3,030.9 7,625.6 12,682.5 (11,124.4) 29,778.0

SIGNIFCANT ACCOUNTING POLICIES

SIGNIFCANT ACCOUNTING POLICIES (Policies) - Jun. 30, 2015	Total	Total
Notes To Consolidated Financial Statements [Abstract]
Organization Consolidation And Presentation Of Financial Statements Disclosure Text Block	A . Basis of Presentation Eversource Energy is a public utility holding company primarily engaged through its wholly owned regulated utility subsidiaries in the energy delivery business. Eversource Energy 's wholly owned regulat ed utility subsidiaries consist of CL&P, NSTAR Electric, PSNH, WMECO, Yankee Gas and NSTAR Gas. Eversource provides energy deliv ery service to approximately 3.6 million electric and natural gas customers through these six regulated utilities in Connecticut, Ma ss achusetts and New Hampshire . On April 30 , 2015, the Company's legal name was changed from Northeast Utilities to Eversource Energy. CL&P, NSTAR Electric, PSNH and WMECO are each doing business as Eversource Energy. The unaudited condensed consolidated financial stateme nts of Eversource , NSTAR Electric and PSNH include the accounts of each o f their respective subsidiaries. Intercompany transactions have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements of Eversource , NSTAR Electric and PSNH and the unaudited condensed financial statements of CL&P and WMECO are herein collectively referred to as the "financial statements." The combined notes to the financial statements have been prepared pursuant to the rules and regulations of the SEC. Certain information and footnote disclosures included in annual financial statements prepared in accordance with GAAP have been omitted pursuant to such rules and regulations. The accompanying financial statements should be read in conjunction with the entirety of this combine d Quarterly Report on Form 10 -Q , the first quarter 2015 combine d Quarterly Report on Form 10 -Q and the 2014 combined Annual Report on Form 10 -K of Eversource , CL&P, NSTAR Electric, PS NH and WMECO, which were filed with the SEC. The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The financial statements contain, in the opinion of management, all adjustments (including normal, recurring adjustments) necessary to present fairly Eversource 's, CL&P's, NSTAR Electric's, PSNH's and WMECO's financial position as of June 30 , 2015 and December 31, 2014, the results of operations and comprehensive income for the three and six months ended June 30 , 2015 and 2014 , and the cash flows for the six months ended June 30, 2015 and 2014 . The results of operations and comprehensive income for the three and six months ended June 30 , 2015 and 2014 and the cash flows for the six months ended June 30, 2015 and 2014 are not necessarily indicative of the results expected for a full year. Eversource consolidates CYAPC and YAEC because CL&P's, NSTAR Electric's, PSNH's and WMECO's combined ownership interest in each of these entities is greater than 50 percent. Intercompany transactions between CL&P, NSTAR Electric, PSNH and WMECO and the CYAPC and YAEC companies have been eliminated in consolidation of the Eversource financial statements. Eversource 's utility subsidiaries ' distribution (including generation ) and transmission businesses and NPT are subject to rate-regulation that is based on cost recovery and meets the criteria for application of accounting guidance for entities with rate-regulated operations , which considers the effect of regulation on the d ifferences in the timing of the recognition of certain revenues and expenses from those of other businesses and industries. See Note 2, "Regulatory Accounting," for further information. Certain reclassifications of prior period data were made in the accompanying financial statements to conform to the current period presentation .
Receivables Policy Text Block	Eversource, including CL&P, NSTAR Electric, PSNH and WMECO, presents its receivables at estimated net realizable value by maintaining a provision for uncollectible accounts. This provision is determined based upon a variety of judgments and factors, including the application of an estimated uncollectible percentage to each receivable aging category. The estimate is based upon historical collection and write-off experience and management's assessment of collectability from customers. Management continuously assesses the collectability of receivables and adjusts collectability estimates based on actual experience. Receivable balances are written off against the provision for uncollectible accounts when the accounts are terminated and these balances are deemed to be uncollectible.
Derivatives Offsetting Fair Value Amounts Policy	The gross fair values of derivative assets and liabilities with the same counterparty are offset and reported as net Derivative Assets or Derivative Liabilities, with current and long-term portions, on the balance sheets.
Fair Value Of Financial Instruments Policy	Fair value measurement guidance is applied to derivative contracts that are not elected or designated as "normal purchases or normal sales" (normal) and to the marketable securities held in trusts. Fair value measurement guidanc e is also applied to valuations of the investments used to calculate the funded status of pension and PBOP plans and nonrecurring fair value measurements of nonfinancial ass ets such as goodwill and AROs, and is also used to estimate the fair value of preferred stock and long-term debt. Fair Value Hierarchy: In measuring fair value, Eversource uses observabl e market data when available in order to minimize the use of unobservable inputs. Inputs used in fair value measurements are categorized into three fair value hierarchy levels for disclosure purposes. The entire fair value measurement is categorized based on the lowest level of input that is significant to the fair value measurement. Eversource evaluates the classification of assets and liabilities measured at fair value on a quarterly basis, and Eversource ' s policy is to recognize transfers between levels of the fair value hierarchy as of the end of the reporting period. The three levels of the fair value hierarchy are described below: Level 1 - Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2 - Inputs are quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs are observable. Level 3 - Quoted market prices are not available. Fair value is derived from valuation techniques in which one or more significant inputs or assumptions are unobservable. Where possible, valuation techniques incorporate observable market inputs that can be validated to external sources such as industry exchanges, including prices of energy and energy-related products. The following methods and assumptions were used to estimate the fair value of each of the following financial instruments: Preferred Stock and Long-Term Debt: The fair value of CL& P's and NSTAR Electric' s preferred stock is based upon pricing models that incorporate interest rates and other market factors, valuations or trades of similar securities and cash flow project ions. The fair value of long-term debt securities is based upon pricing models that incorporate quoted market prices for those issues or similar issues adjusted for market conditions, credit ratings of the respective companies and treasury benchmark yields. The fair values provided in the tables below are classified as Level 2 within the fair value hierarchy .	Derivative contracts classified as Level 2 in the fair value hierarchy relate to the financial contracts for natural gas futures. Prices are obtained from broker quotes and are based on actual market activity. The contracts are valued using NYMEX natural gas prices . Valuations of these contracts also incorporate discount rates using the yield curve approach. The fair value of derivative contracts classified as Level 3 utilizes significant unobservable inputs. The fair value is modeled using income techniques, such as discounted cash flow valuations adjusted for assumptions relating to exit price. Significant observable inputs for valuations of these contracts include energy and energy-related product prices in future years for which quoted prices in an active market exist. Fair value measurements categorized in Level 3 of the fair value hierarchy are prepared by individuals with expertise in valuation techniques, pricing of energy and energy-related products, and accounting requirements. The future power and capacity prices for periods that are not quoted in an active market or established at auction are based on available market data and are escalated based on estimates of inflation to address the full time period of the contract. Valuations of derivative contracts using a discounted cash flow methodology include assumptions regarding the timing and likelihood of scheduled payments and also reflect non-performance risk, including credit, using the default probability approach based on the counterparty ' s credit rating for assets and the Company ' s credit rating for liabilities. Valuations incorporate estimates of premiums or discounts that would be required by a market participant to arrive at an exit price, using historical market transactions adjusted for the terms of the contract.
Other Taxes Policy	Gross receipts taxes levied by the state of Connecticut are collected by CL&P and Yankee Gas from their respective customers. These gross receipts taxes are shown separately with collections in Operating Revenues and payments in Taxes Other Than Income Taxes on the statements of income Certain sales taxes are collected by Eversource's companies that serve customers in Connecticut and Massachusetts as agents for state and local governments and are recorded on a net basis with no impact on the statements of income.
Public Utilities Policy Text Block	Eversource's Regulated companies are subject to rate-regulation that is based on cost recovery and meets the criteria for application of accounting guidance for rate-regulated operations , which consider the effect of regulation o n the timing of the recognition of certain revenues and expenses . The Regulated companies' financial statements reflect the effects of the rate-making process. The ra tes charged to the customers of Eversource 's Regulated companies are designed to collect each company's costs to provide service, including a return on investment. Management believes it is probable that each of the Regulated companies will recover their respective investments in long-lived assets, including regulatory assets. If management were to determine that it could no longer apply the accounting guidance applicable to rate-regulated enterprises to any of the Regulated companies' operations, or that management could not conclude it is probable that costs would be recovered from customers in future rates, the costs would be charged to net income in the period in which the determination is made.
Derivatives Policy Text Block	Many of the derivative contracts meet the definition of, and are designated as, normal and qualify for accrual accounting under the applicable accounting guidance. The costs and benefits of derivative contracts that meet the definition of normal are recognized in Operating Expenses or Operating Revenues on the statements of income, as applicable, as electricity or natural gas is delivered. Derivative contracts that are not designated as normal are recorded at fair value as current or long-term Derivative Assets or Derivative Liabilities on the balance sheets. For the Regulated companies, regulatory assets or regulatory liabilities are recorded to offset the fair values of derivatives, as contract settlement amount s are recovered from, or refunded to, customers in their respective energy supply rates.
Marketable Securities Policy	U.S. government issued debt securities are valued using market approaches that incorporate transactions for the same or similar bonds and adjustments for yields and maturity dates. Corporate debt securities are valued using a market approach, utilizing recent trades of the same or similar instrument and also incorporating yield curves, credit spreads and specific bond terms and conditions. Asset-backed debt securities include collateralized mortgage obligations, commercial mortgage backed securities, and securities collateralized by auto loans, credit card loans or receivables. Asset-backed debt securities are valued using recent trades of similar instruments, prepayment assumptions, yield curves, issuance and maturity dates, and tranche information. Municipal bonds are valued using a market approach that incorporates reported trades and benchmark yields. Other fixed income securities are valued using pricing models, quoted prices of securities with similar characteristics, and discounted cash flows.
Environmental Costs Policy	Environmental Matters General: E versource , CL&P, NSTAR Electric, PSNH and WMECO are subject to environmental laws and regulations intended to mitigate or remove the effect of past operations and improve or maintain the quality of the environment. These laws and regulations require the removal or the remedy of the effect on the environment of the disposal or release of certain specified hazardous substances at current and former operating sites. E versource , CL&P, NSTAR Electric , PSNH and WMECO have an active environmental auditing and training program and believe that they are substantially in compliance with all enacted laws and regulations.
Earnings Per Share Policy Text Block	Basic EPS is computed based upon the weighted average number of common shares outstanding during each period. Diluted EPS is compu ted on the basis of the weighted average number of common shares outstanding plus the potential dilut ive effect of certain share-based compensation awards as if they were converted into common shares . RSUs and performance shares are included in basic weighted average common shares outstanding as of the date that all necessary vesting conditions have been satisfied. The dilutive effect of unvested RSUs and performance shares is calculated using the treasury stock method. Assumed proceeds of the se units under the treasury stock method consist of the remaining compensation cost to be recognized and a theoretical tax benefit. The theoretical tax benefit is calculated as the tax impact of the intrinsic value of the units (the difference between the market value of the average units outstanding for the period, using the average market price during the period, and the grant date market value). The dilutive effect of stock options to purchase common shares is also calculated using the treasury stock method. Assumed proceeds for stock options consist of cash proceeds that would be received upon exercise, and a theoretical tax benefit. The theoretical tax benefit is calculated as the tax impact of the intrinsic value of the stock options (the difference between the market value of the average stock options outstanding for the period, using the average market price during the period, and the exercise price).
Segment Reporting Policy Policy Text Block	SEGMENT INFORMATION Presentation: Eversource is organized between the Electric Distribution, Electric Transmission and Natural Gas Distribution reportable segments and Other based on a combination of factors, including the characteristics of each segments ' products and services, the sources of operating revenues and expenses and the regulatory environment i n which each segment operates. These reportable segments rep resent substantially all of Eversource 's total consolidated revenues. Revenues from the sale of electricity and natural gas primarily are derived from residential, commercial and industrial customers and are not dependent on any single customer. The Electric Distribution reportable segment includes the generation activities of PSNH and WMECO. The remainder of Eversource ' s operations is presented as Other in the tables below and primarily consists of 1) the equity in earnings of E versource parent from its subsidiaries and intercompany interest income, both of which are eliminated in consolidation, and interest e xpense related to the debt of Eversource parent, 2) the revenues and ex penses of Eversource Service , most of which are eliminated in consolidation, 3) the operations of CYAPC and YAEC, and 4 ) the results of other un regulated subsidiaries, which are not part of its core business. Cash flows used for investments in plant included in the segment information below are cash capital expenditures that do not include amounts incurred but not paid, cost of removal, AFU DC related to equity funds, and the capitalized portions of pension e xpense.

Provision for Uncollectible Acc

Provision for Uncollectible Accounts (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Accounts Notes Loans And Financing Receivable Text Block	Total Provision for Uncollectible Accounts Uncollectible Hardship (Millions of Dollars) As of June 30, 2015 As of December 31, 2014 As of June 30, 2015 As of December 31, 2014 Eversource $ 209.8 $ 175.3 $ 106.2 $ 91.5 CL&P 100.5 84.3 84.7 74.0 NSTAR Electric 46.3 40.7 - - PSNH 9.5 7.7 - - WMECO 12.1 9.9 7.2 6.2

Other Taxes (Tables)

Other Taxes (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
State Of Connecticut Gross Earnings Taxes [Table Text Block]	For the Three Months Ended For the Six Months Ended (Millions of Dollars) June 30, 2015 June 30, 2014 June 30, 2015 June 30, 2014 Eversource $ 33.2 $ 35.2 $ 75.1 $ 79.6 CL&P 29.5 30.9 62.5 66.5

Supplemental Cash Flow Informat

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]	G. Supplemental Cash Flow Information Non-cash investing activities include plant additions included in Accounts Payable as follows: (Millions of Dollars) As of June 30, 2015 As of June 30, 2014 Eversource $ 142.3 $ 125.5 CL&P 47.2 54.0 NSTAR Electric 29.5 21.6 PSNH 25.6 14.8 WMECO 13.7 9.9

REGULATORY ACCOUNTING (Tables)

REGULATORY ACCOUNTING (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Regulatory Assets Text Block	As of June 30, 2015 As of December 31, 2014 (Millions of Dollars) Eversource Eversource Benefit Costs $ 1,980.0 $ 2,016.0 Derivative Liabilities 423.7 425.5 Income Taxes, Net 631.5 635.3 Storm Restoration Costs 484.3 502.8 Goodwill-related 495.1 505.4 Regulatory Tracker Mechanisms 430.7 350.5 Contractual Obligations - Yankee Companies 124.8 123.8 Other Regulatory Assets 156.3 167.3 Total Regulatory Assets 4,726.4 4,726.6 Less: Current Portion 709.7 672.5 Total Long-Term Regulatory Assets $ 4,016.7 $ 4,054.1 As of June 30, 2015 As of December 31, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH WMECO CL&P Electric PSNH WMECO Benefit Costs $ 443.3 $ 496.1 $ 175.1 $ 85.9 $ 445.4 $ 515.9 $ 174.3 $ 85.0 Derivative Liabilities 420.2 2.2 - - 410.9 4.5 - - Income Taxes, Net 438.9 84.0 34.8 30.7 437.7 83.7 38.0 35.5 Storm Restoration Costs 298.4 117.1 41.1 27.7 319.6 103.7 47.7 31.8 Goodwill-related - 425.1 - - - 433.9 - - Regulatory Tracker Mechanisms 44.8 255.0 84.3 36.0 16.1 141.4 103.5 33.0 Other Regulatory Assets 79.6 77.2 35.7 12.7 66.1 94.7 41.3 12.9 Total Regulatory Assets 1,725.2 1,456.7 371.0 193.0 1,695.8 1,377.8 404.8 198.2 Less: Current Portion 263.7 258.5 88.8 54.9 220.3 198.7 111.7 51.9 Total Long-Term Regulatory Assets $ 1,461.5 $ 1,198.2 $ 282.2 $ 138.1 $ 1,475.5 $ 1,179.1 $ 293.1 $ 146.3
Schedule Of Regulatory Liabilities Text Block	As of June 30, 2015 As of December 31, 2014 (Millions of Dollars) Eversource Eversource Cost of Removal $ 434.9 $ 439.9 Regulatory Tracker Mechanisms 198.0 192.3 AFUDC - Transmission 66.2 67.1 Other Regulatory Liabilities 20.2 50.8 Total Regulatory Liabilities 719.3 750.1 Less: Current Portion 208.5 235.0 Total Long-Term Regulatory Liabilities $ 510.8 $ 515.1 As of June 30, 2015 As of December 31, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH WMECO CL&P Electric PSNH WMECO Cost of Removal $ 13.5 $ 261.5 $ 49.1 $ 2.8 $ 19.7 $ 258.3 $ 50.3 $ 1.1 Regulatory Tracker Mechanisms 115.6 2.9 4.8 17.0 122.6 20.7 14.2 22.3 AFUDC - Transmission 52.2 5.0 - 9.0 53.6 4.4 - 9.1 Other Regulatory Liabilities 12.5 2.2 2.0 0.9 10.1 28.9 2.9 0.8 Total Regulatory Liabilities 193.8 271.6 55.9 29.7 206.0 312.3 67.4 33.3 Less: Current Portion 122.6 5.0 5.6 16.8 124.7 49.6 16.0 22.5 Total Long-Term Regulatory Liabilities $ 71.2 $ 266.6 $ 50.3 $ 12.9 $ 81.3 $ 262.7 $ 51.4 $ 10.8

PROPERTY, PLANT AND ACCUMULAT25

PROPERTY, PLANT AND ACCUMULATED DEPRECIATION (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule of Public Utility Property, Plant, and Equipment [Text Block]	As of June 30, 2015 As of December 31, 2014 (Millions of Dollars) Eversource Eversource Distribution - Electric $ 12,701.6 $ 12,495.2 Distribution - Natural Gas 2,625.9 2,595.4 Transmission 7,196.3 6,930.7 Generation 1,175.9 1,170.9 Electric and Natural Gas Utility 23,699.7 23,192.2 Other (1) 547.5 551.3 Property, Plant and Equipment, Gross 24,247.2 23,743.5 Less: Accumulated Depreciation Electric and Natural Gas Utility (5,950.4) (5,777.8) Other (238.4) (231.8) Total Accumulated Depreciation (6,188.8) (6,009.6) Property, Plant and Equipment, Net 18,058.4 17,733.9 Construction Work in Progress 1,020.8 913.1 Total Property, Plant and Equipment, Net $ 19,079.2 $ 18,647.0 As of June 30, 2015 As of December 31, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH WMECO CL&P Electric PSNH WMECO Distribution $ 5,245.3 $ 4,954.7 $ 1,744.8 $ 796.8 $ 5,158.8 $ 4,895.5 $ 1,696.7 $ 784.2 Transmission 3,455.5 1,965.2 821.2 906.4 3,274.0 1,928.5 789.7 891.0 Generation - - 1,141.5 34.4 - - 1,136.5 34.4 Property, Plant and Equipment, Gross 8,700.8 6,919.9 3,707.5 1,737.6 8,432.8 6,824.0 3,622.9 1,709.6 Less: Accumulated Depreciation (1,975.9) (1,824.9) (1,127.6) (309.2) (1,928.0) (1,761.4) (1,090.0) (297.4) Property, Plant and Equipment, Net 6,724.9 5,095.0 2,579.9 1,428.4 6,504.8 5,062.6 2,532.9 1,412.2 Construction Work in Progress 209.7 356.7 135.0 79.8 304.9 272.8 102.9 49.1 Total Property, Plant and Equipment, Net $ 6,934.6 $ 5,451.7 $ 2,714.9 $ 1,508.2 $ 6,809.7 $ 5,335.4 $ 2,635.8 $ 1,461.3

DERIVATIVE INSTRUMENTS (Tables)

DERIVATIVE INSTRUMENTS (Tables)	6 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Derivative Instruments In Statement Of Financial Position Fair Value Text Block	As of June 30, 2015 As of December 31, 2014 Commodity Supply Net Amount Commodity Supply Net Amount and Price Risk Recorded as and Price Risk Recorded as (Millions of Dollars) Management Netting (1) a Derivative Management Netting (1) a Derivative Current Derivative Assets: Level 3: Eversource $ 16.5 $ (10.4) $ 6.1 $ 16.2 $ (6.6) $ 9.6 CL&P 16.5 (10.4) 6.1 16.1 (6.6) 9.5 NSTAR Electric - - - 0.1 - 0.1 Long-Term Derivative Assets: Level 3: Eversource $ 69.1 $ (23.9) $ 45.2 $ 93.5 $ (19.2) $ 74.3 CL&P 68.7 (23.9) 44.8 93.5 (19.2) 74.3 NSTAR Electric 0.4 - 0.4 - - - Current Derivative Liabilities: Level 2: Eversource $ (1.5) $ 0.2 $ (1.3) $ (9.8) $ - $ (9.8) Level 3: Eversource (92.7) - (92.7) (90.0) - (90.0) CL&P (90.9) - (90.9) (88.5) - (88.5) NSTAR Electric (1.8) - (1.8) (1.5) - (1.5) Long-Term Derivative Liabilities: Level 2: Eversource $ - $ - $ - $ (0.3) $ - $ (0.3) Level 3: Eversource (381.0) - (381.0) (409.3) - (409.3) CL&P (380.2) - (380.2) (406.2) - (406.2) NSTAR Electric (0.8) - (0.8) (3.1) - (3.1)
Rollforward Of Net Derivative Asset Liabilities Valued Using Unobservable Inputs [Table Text Block]	For the Three Months Ended June 30, 2015 2014 NSTAR NSTAR (Millions of Dollars) Eversource CL&P Electric Eversource CL&P Electric Derivatives, Net: Fair Value as of Beginning of Period $ (406.8) $ (403.3) $ (3.5) $ (564.3) $ (557.0) $ (7.3) Net Realized/Unrealized Gains/(Losses) Included in Regulatory Assets and Liabilities (37.1) (36.8) (0.3) 111.8 112.2 (0.4) Settlements 21.5 19.9 1.6 21.6 20.2 1.4 Fair Value as of End of Period $ (422.4) $ (420.2) $ (2.2) $ (430.9) $ (424.6) $ (6.3) For the Six Months Ended June 30, 2015 2014 NSTAR NSTAR (Millions of Dollars) Eversource CL&P Electric Eversource CL&P Electric Derivatives, Net: Fair Value as of Beginning of Period $ (415.4) $ (410.9) $ (4.5) $ (635.2) $ (630.6) $ (7.3) Net Realized/Unrealized Gains/(Losses) Included in Regulatory Assets and Liabilities (49.2) (48.9) (0.3) 161.3 164.5 (0.5) Settlements 42.2 39.6 2.6 43.0 41.5 1.5 Fair Value as of End of Period $ (422.4) $ (420.2) $ (2.2) $ (430.9) $ (424.6) $ (6.3)
Fairvalueinputsliabilitiesquantitativeinformationtabletextblock	As of June 30, 2015 As of December 31, 2014 Range Period Covered Range Period Covered Energy Prices: Eversource, CL&P $ 45 per MWh 2020 $ 52 per MWh 2020 Capacity Prices: Eversource $ 10.05 - 12.60 per kW-Month 2016 - 2026 $ 5.30 - 12.98 per kW-Month 2016 - 2026 CL&P $ 10.81 - 12.60 per kW-Month 2019 - 2026 $ 11.08 - 12.98 per kW-Month 2018 - 2026 NSTAR Electric $ 10.05 - 10.81 per kW-Month 2016 - 2019 $ 5.30 - 11.10 per kW-Month 2016 - 2019 Forward Reserve: Eversource, CL&P $ 2.40 per kW-Month 2015 - 2024 $ 5.80 - 9.50 per kW-Month 2015 - 2024 REC Prices: Eversource, NSTAR Electric $ 46 - 51 per REC 2015 - 2018 $ 38 - 56 per REC 2015 - 2018

MARKETABLE SECURITIES (Tables)

MARKETABLE SECURITIES (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Available For Sale Securities Reconciliation [Table TextBlock]	As of June 30, 2015 As of December 31, 2014 Pre-Tax Pre-Tax Pre-Tax Pre-Tax Amortized Unrealized Unrealized Amortized Unrealized Unrealized (Millions of Dollars) Cost Gains Losses Fair Value Cost Gains Losses Fair Value Eversource Debt Securities (1) $ 315.3 $ 4.9 $ (0.6) $ 319.6 $ 313.0 $ 7.5 $ (0.3) $ 320.2 Equity Securities (1) 216.5 72.9 (1.2) 288.2 160.6 73.3 - 233.9 WMECO Debt Securities (2) 58.3 - - 58.3 58.2 - (0.1) 58.1
Investments Classified by Contractual Maturity Date [Table Text Block]	Eversource WMECO Amortized Amortized (Millions of Dollars) Cost Fair Value Cost Fair Value Less than one year (1) $ 66.1 $ 66.1 $ 38.4 $ 38.4 One to five years 70.4 70.8 16.2 16.2 Six to ten years 60.1 61.2 0.6 0.6 Greater than ten years 118.7 121.5 3.1 3.1 Total Debt Securities $ 315.3 $ 319.6 $ 58.3 $ 58.3
Fair Value Heirarchy [Table Text Block]	Eversource WMECO (Millions of Dollars) As of June 30, 2015 As of December 31, 2014 As of June 30, 2015 As of December 31, 2014 Level 1: Mutual Funds and Equities $ 303.1 $ 319.0 $ - $ - Money Market Funds 26.4 24.9 2.1 4.3 Total Level 1 $ 329.5 $ 343.9 $ 2.1 $ 4.3 Level 2: U.S. Government Issued Debt Securities (Agency and Treasury) $ 38.6 $ 51.3 $ - $ - Corporate Debt Securities 60.1 49.1 13.6 14.7 Asset-Backed Debt Securities 32.0 54.1 10.0 14.5 Municipal Bonds 126.9 116.3 10.8 13.0 Other Fixed Income Securities 35.6 24.5 21.8 11.6 Total Level 2 $ 293.2 $ 295.3 $ 56.2 $ 53.8 Total Marketable Securities $ 622.7 $ 639.2 $ 58.3 $ 58.1

Pension Benefits and Postreti28

Pension Benefits and Postretirement Benefits Other Than Pensions (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Net Benefit Costs [Table Text Block]	Pension and SERP Pension and SERP Eversource For the Three Months Ended For the Six Months Ended (Millions of Dollars) June 30, 2015 (1) June 30, 2014 June 30, 2015 (1) June 30, 2014 Service Cost $ 22.8 $ 19.1 $ 45.9 $ 41.5 Interest Cost 56.9 56.3 113.3 113.0 Expected Return on Plan Assets (83.9) (77.7) (168.2) (155.4) Actuarial Loss 36.5 31.7 75.5 64.7 Prior Service Cost 0.9 1.1 1.8 2.1 Total Net Periodic Benefit Expense $ 33.2 $ 30.5 $ 68.3 $ 65.9 Capitalized Pension Expense $ 9.8 $ 8.7 $ 21.1 $ 18.4 PBOP PBOP Eversource For the Three Months Ended For the Six Months Ended (Millions of Dollars) June 30, 2015 (1) June 30, 2014 June 30, 2015 (1) June 30, 2014 Service Cost $ 3.9 $ 3.2 $ 8.1 $ 6.3 Interest Cost 11.7 12.1 23.6 24.7 Expected Return on Plan Assets (16.9) (15.8) (33.7) (31.6) Actuarial Loss 1.7 3.0 3.4 6.0 Prior Service Credit (0.2) (0.7) (0.2) (1.4) Total Net Periodic Benefit Expense $ 0.2 $ 1.8 $ 1.2 $ 4.0 Capitalized PBOP Expense/(Income) $ (0.1) $ 0.4 $ - $ 0.8 Pension and SERP For the Three Months Ended June 30, 2015 For the Three Months Ended June 30, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH (1) WMECO CL&P Electric PSNH WMECO Service Cost $ 6.2 $ 3.7 $ 3.1 $ 1.0 $ 5.0 $ 3.0 $ 2.3 $ 0.8 Interest Cost 12.9 10.0 6.1 2.6 12.4 10.3 5.8 2.5 Expected Return on Plan Assets (19.8) (17.5) (10.1) (4.7) (18.7) (15.7) (9.3) (4.4) Actuarial Loss 8.0 8.7 2.9 1.6 8.2 5.9 2.8 1.7 Prior Service Cost 0.4 - 0.1 0.1 0.5 - 0.1 0.1 Total Net Periodic Benefit Expense $ 7.7 $ 4.9 $ 2.1 $ 0.6 $ 7.4 $ 3.5 $ 1.7 $ 0.7 Intercompany Allocations $ 5.8 $ 3.4 $ 1.6 $ 1.1 $ 7.5 $ 1.4 $ 2.1 $ 1.4 Capitalized Pension Expense $ 4.7 $ 2.7 $ 0.9 $ 0.5 $ 4.4 $ 1.0 $ 0.8 $ 0.6 Pension and SERP For the Six Months Ended June 30, 2015 For the Six Months Ended June 30, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH (1) WMECO CL&P Electric PSNH WMECO Service Cost $ 12.2 $ 7.5 $ 6.0 $ 2.2 $ 10.2 $ 7.6 $ 5.1 $ 1.9 Interest Cost 25.4 20.1 12.1 5.2 25.7 20.6 12.3 5.2 Expected Return on Plan Assets (39.4) (35.1) (20.2) (9.4) (38.0) (31.5) (19.5) (9.0) Actuarial Loss 16.2 18.4 5.8 3.2 17.3 11.7 6.0 3.5 Prior Service Cost 0.8 - 0.2 0.1 0.9 - 0.3 0.2 Total Net Periodic Benefit Expense $ 15.2 $ 10.9 $ 3.9 $ 1.3 $ 16.1 $ 8.4 $ 4.2 $ 1.8 Intercompany Allocations $ 12.2 $ 6.9 $ 3.4 $ 2.3 $ 14.3 $ 3.8 $ 4.2 $ 2.7 Capitalized Pension Expense $ 9.4 $ 5.9 $ 1.7 $ 1.0 $ 9.3 $ 2.9 $ 1.7 $ 1.4 PBOP For the Three Months Ended June 30, 2015 For the Three Months Ended June 30, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH (1) WMECO CL&P Electric PSNH WMECO Service Cost $ 0.5 $ 1.3 $ 0.3 $ 0.1 $ 0.5 $ 0.8 $ 0.3 $ 0.1 Interest Cost 1.8 4.7 1.0 0.3 1.9 4.8 1.0 0.4 Expected Return on Plan Assets (2.8) (6.9) (1.5) (0.6) (2.5) (6.5) (1.3) (0.6) Actuarial Loss/(Gain) 0.2 0.4 0.1 - 1.0 (0.2) 0.6 0.1 Prior Service Credit - (0.1) - - - (0.5) - - Total Net Periodic Benefit Expense/(Income) $ (0.3) $ (0.6) $ (0.1) $ (0.2) $ 0.9 $ (1.6) $ 0.6 $ - Intercompany Allocations $ 0.4 $ 0.2 $ 0.1 $ 0.1 $ 1.1 $ - $ 0.3 $ 0.2 Capitalized PBOP Expense/(Income) $ (0.1) $ (0.2) $ - $ - $ 0.5 $ (0.5) $ 0.2 $ - PBOP For the Six Months Ended June 30, 2015 For the Six Months Ended June 30, 2014 NSTAR NSTAR (Millions of Dollars) CL&P Electric PSNH (1) WMECO CL&P Electric PSNH WMECO Service Cost $ 1.1 $ 2.7 $ 0.7 $ 0.2 $ 1.1 $ 1.6 $ 0.7 $ 0.2 Interest Cost 3.5 9.5 1.9 0.8 4.0 9.7 2.1 0.8 Expected Return on Plan Assets (5.5) (13.7) (3.0) (1.3) (5.2) (13.0) (2.7) (1.1) Actuarial Loss/(Gain) 0.3 1.2 0.3 - 2.1 (0.3) 1.1 0.2 Prior Service Credit - (0.1) - - - (0.9) - - Total Net Periodic Benefit Expense/(Income) $ (0.6) $ (0.4) $ (0.1) $ (0.3) $ 2.0 $ (2.9) $ 1.2 $ 0.1 Intercompany Allocations $ 0.9 $ 0.4 $ 0.2 $ 0.2 $ 2.2 $ 0.1 $ 0.6 $ 0.4 Capitalized PBOP Expense/(Income) $ (0.1) $ (0.1) $ 0.1 $ (0.1) $ 1.0 $ (1.0) $ 0.4 $ 0.1 (1) Amounts exclude approximately $0.8 million and $1.6 million for the three and six months ended June 30, 2015, respectively, that represented amounts included in other deferred debits.

Environmental Matters (Tables)

Environmental Matters (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Environmental Loss Contingencies By Site Text Block	As of June 30, 2015 As of December 31, 2014 Reserve Reserve Number of Sites (in millions) Number of Sites (in millions) Eversource 65 $ 46.2 65 $ 43.3 CL&P 15 4.9 16 3.8 NSTAR Electric 14 2.3 13 1.1 PSNH 12 3.4 13 5.2 WMECO 4 0.6 4 0.5

Guarantees and Indemnifications

Guarantees and Indemnifications (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Guarantee Obligations Text Block	Maximum Exposure Company Description (in millions) Expiration Dates On behalf of subsidiaries: Various Surety Bonds (1) $ 33.8 2015 - 2016 Eversource Service and Rocky River Realty Company Lease Payments for Vehicles and Real Estate $ 12.7 2019 and 2024 On behalf of external parties: Purchaser of E.S. Boulos Company and a bonding company E.S. Boulos Company Indemnification $ 42.1 2016 and 2020

FAIR VALUE OF FINANCIAL INSTR31

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Fair Value By Balance Sheet Grouping Text Block	As of June 30, 2015 As of December 31, 2014 Eversource Carrying Fair Carrying Fair (Millions of Dollars) Amount Value Amount Value Preferred Stock Not Subject to Mandatory Redemption $ 155.6 $ 154.8 $ 155.6 $ 153.6 Long-Term Debt 8,968.5 9,329.9 8,851.6 9,451.2 As of June 30, 2015 CL&P NSTAR Electric PSNH WMECO Carrying Fair Carrying Fair Carrying Fair Carrying Fair (Millions of Dollars) Amount Value Amount Value Amount Value Amount Value Preferred Stock Not Subject to Mandatory Redemption $ 116.2 $ 113.0 $ 43.0 $ 41.8 $ - $ - $ - $ - Long-Term Debt 2,975.1 3,242.9 1,792.7 1,916.6 1,076.3 1,133.0 628.0 658.0 As of December 31, 2014 CL&P NSTAR Electric PSNH WMECO Carrying Fair Carrying Fair Carrying Fair Carrying Fair (Millions of Dollars) Amount Value Amount Value Amount Value Amount Value Preferred Stock Not Subject to Mandatory Redemption $ 116.2 $ 112.0 $ 43.0 $ 41.6 $ - $ - $ - $ - Long-Term Debt 2,842.0 3,214.5 1,797.4 1,993.5 1,076.3 1,137.9 628.5 689.4

ACCUMULATED OTHER COMPREHENSI32

ACCUMULATED OTHER COMPREHENSIVE INCOME (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Accumulated Other Comprehensive Income Loss Table Text Block	For the Six Months Ended June 30, 2015 For the Six Months Ended June 30, 2014 Qualified Unrealized Qualified Unrealized Cash Flow Gains/(Losses) Defined Cash Flow Gains on Defined Eversource Hedging on Marketable Benefit Hedging Marketable Benefit (Millions of Dollars) Instruments Securities Plans Total Instruments Securities Plans Total Balance as of Beginning of Period $ (12.4) $ 0.7 $ (62.3) $ (74.0) $ (14.4) $ 0.4 $ (32.0) $ (46.0) OCI Before Reclassifications - (1.1) (0.4) (1.5) - 0.5 1.2 1.7 Amounts Reclassified from AOCI 1.0 - 2.5 3.5 1.0 - 1.8 2.8 Net OCI 1.0 (1.1) 2.1 2.0 1.0 0.5 3.0 4.5 Balance as of End of Period $ (11.4) $ (0.4) $ (60.2) $ (72.0) $ (13.4) $ 0.9 $ (29.0) $ (41.5)

COMMON SHARES (Tables)

COMMON SHARES (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule of Stock by Class [Text Block]	11 . COMMON SHARES The following table sets fo rth the E ve r s ource parent common shares and the shares of common stock of CL&P, NSTAR Electric , PSNH and WMECO that were authorized and issued and the respective per share par values : Shares Authorized as of Per Share June 30, 2015 and Issued as of Par Value December 31, 2014 June 30, 2015 December 31, 2014 Eversource $ 5 380,000,000 333,833,308 333,359,172 CL&P $ 10 24,500,000 6,035,205 6,035,205 NSTAR Electric $ 1 100,000,000 100 100 PSNH $ 1 100,000,000 301 301 WMECO $ 25 1,072,471 434,653 434,653 As of June 30 , 2015 and December 31, 2014 , there were 16,671,366 and 16,375,835 E versource common shares held as treasury shares, respectively. As of June 30 , 2015 and December 31, 2014 , Eversource common sha res outstanding were 317,161,942 and 316 , 983 , 337 , respectively. In May 2015, the Company repurchased 532,521 treasury shares at a share price of $47.94.

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	3 Months Ended
	Jun. 30, 2015
Notes To Consolidated Financial Statements [Abstract]
Schedule Of Earnings Per Share Basic And Diluted [Table Text Block]	Eversource For the Three Months Ended For the Six Months Ended (Millions of Dollars, except share information) June 30, 2015 June 30, 2014 June 30, 2015 June 30, 2014 Net Income Attributable to Controlling Interest $ 207.5 $ 127.4 $ 460.8 $ 363.3 Weighted Average Common Shares Outstanding: Basic 317,613,166 315,950,510 317,352,004 315,742,511 Dilutive Effect 946,402 1,162,291 1,173,374 1,259,950 Diluted 318,559,568 317,112,801 318,525,378 317,002,461 Basic and Diluted EPS $ 0.65 $ 0.40 $ 1.45 $ 1.15

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	3 Months Ended
	Jun. 30, 2015
Segment Reporting Information [Line Items]
Schedule Of Segment Reporting Information By Segment Text Block	For the Three Months Ended June 30, 2015 Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total Operating Revenues $ 1,382.7 $ 186.0 $ 267.8 $ 203.7 $ (223.1) $ 1,817.1 Depreciation and Amortization (98.5) (17.7) (39.7) (7.1) 0.5 (162.5) Other Operating Expenses (1,052.1) (150.2) (73.1) (190.7) 223.5 (1,242.6) Operating Income 232.1 18.1 155.0 5.9 0.9 412.0 Interest Expense (45.6) (9.1) (26.3) (12.4) 1.1 (92.3) Other Income, Net 5.5 0.3 5.1 220.1 (218.1) 12.9 Net Income Attributable to Controlling Interest $ 120.9 $ 5.3 $ 80.4 $ 217.0 $ (216.1) $ 207.5 For the Six Months Ended June 30, 2015 Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total Operating Revenues $ 3,142.8 $ 693.4 $ 516.8 $ 443.7 $ (466.2) $ 4,330.5 Depreciation and Amortization (257.6) (35.9) (80.1) (14.3) 1.0 (386.9) Other Operating Expenses (2,395.0) (538.7) (147.2) (419.9) 466.7 (3,034.1) Operating Income 490.2 118.8 289.5 9.5 1.5 909.5 Interest Expense (93.2) (18.1) (53.9) (24.1) 2.2 (187.1) Other Income, Net 7.6 0.1 8.1 535.0 (532.2) 18.6 Net Income Attributable to Controlling Interest $ 251.4 $ 61.0 $ 147.0 $ 529.9 $ (528.5) $ 460.8 Cash Flows Used for Investments in Plant $ 319.8 $ 67.5 $ 328.7 $ 24.4 $ - $ 740.4 For the Three Months Ended June 30, 2014 Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total Operating Revenues $ 1,261.8 $ 195.5 $ 206.9 $ 184.7 $ (171.3) $ 1,677.6 Depreciation and Amortization (89.3) (16.9) (37.0) (7.7) 2.3 (148.6) Other Operating Expenses (991.5) (166.5) (71.0) (174.9) 168.9 (1,235.0) Operating Income 181.0 12.1 98.9 2.1 (0.1) 294.0 Interest Expense (47.2) (8.7) (28.8) (9.1) 1.3 (92.5) Other Income, Net 2.9 - 2.7 137.7 (137.8) 5.5 Net Income Attributable to Controlling Interest $ 83.4 $ 2.0 $ 43.9 $ 133.3 $ (135.2) $ 127.4 For the Six Months Ended June 30, 2014 Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total Operating Revenues $ 2,847.8 $ 628.3 $ 458.9 $ 356.9 $ (323.7) $ 3,968.2 Depreciation and Amortization (238.2) (34.6) (74.0) (14.7) 4.1 (357.4) Other Operating Expenses (2,202.4) (487.9) (137.3) (340.3) 318.8 (2,849.1) Operating Income 407.2 105.8 247.6 1.9 (0.8) 761.7 Interest Expense (94.6) (17.1) (54.3) (18.7) 2.2 (182.5) Other Income, Net 4.3 0.1 4.2 432.4 (433.8) 7.2 Net Income Attributable to Controlling Interest $ 195.6 $ 54.1 $ 118.8 $ 424.9 $ (430.1) $ 363.3 Cash Flows Used for Investments in Plant $ 335.6 $ 68.6 $ 289.3 $ 30.5 $ - $ 724.0 The following table summarizes Eversource's segmented total assets: Eversource Electric Natural Gas Electric (Millions of Dollars) Distribution Distribution Transmission Other Eliminations Total As of June 30, 2015 $ 17,872.9 $ 2,933.4 $ 7,589.7 $ 12,455.7 $ (10,971.8) $ 29,879.9 As of December 31, 2014 17,563.4 3,030.9 7,625.6 12,682.5 (11,124.4) 29,778.0

Basis of Presentation (Details)

Basis of Presentation (Details)	3 Months Ended
	Jun. 30, 2015
Description of Consolidation of Yankee Companies	Eversource consolidates CYAPC and YAEC because CL&P's, NSTAR Electric's, PSNH's and WMECO's combined ownership interest in each of these entities is greater than 50 percent. Intercompany transactions between CL&P, NSTAR Electric, PSNH and WMECO and the CYAPC and YAEC companies have been eliminated in consolidation of the Eversource financial statements.

Provision for Uncollectible A37

Provision for Uncollectible Accounts (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Accounts Notes And Loans Receivable [Line Items]
Allowance For Doubtful Accounts Receivable Current	$ 209.8	$ 175.3
Uncollectible Hardship Accounts Receivable Reserve	106.2	91.5
The Connecticut Light And Power Company [Member]
Accounts Notes And Loans Receivable [Line Items]
Allowance For Doubtful Accounts Receivable Current	100.5	84.3
Uncollectible Hardship Accounts Receivable Reserve	84.7	74
NSTAR Electric Company [Member]
Accounts Notes And Loans Receivable [Line Items]
Allowance For Doubtful Accounts Receivable Current	46.3	40.7
Public Service Company Of New Hampshire [Member]
Accounts Notes And Loans Receivable [Line Items]
Allowance For Doubtful Accounts Receivable Current	9.5	7.7
Western Massachusetts Electric Company [Member]
Accounts Notes And Loans Receivable [Line Items]
Allowance For Doubtful Accounts Receivable Current	12.1	9.9
Uncollectible Hardship Accounts Receivable Reserve	$ 7.2	$ 6.2

Other Taxes (Details)

Other Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Excise And Sales Taxes	$ 33.2	$ 35.2	$ 75.1	$ 79.6
The Connecticut Light And Power Company [Member]
Excise And Sales Taxes	$ 29.5	$ 30.9	$ 62.5	$ 66.5

Supplemental Cash Flow Inform39

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Capital Expenditures Incurred But Not Yet Paid	$ 142.3	$ 125.5
The Connecticut Light And Power Company [Member]
Capital Expenditures Incurred But Not Yet Paid	47.2	54
NSTAR Electric Company [Member]
Capital Expenditures Incurred But Not Yet Paid	29.5	21.6
Public Service Company Of New Hampshire [Member]
Capital Expenditures Incurred But Not Yet Paid	25.6	14.8
Western Massachusetts Electric Company [Member]
Capital Expenditures Incurred But Not Yet Paid	$ 13.7	$ 9.9

Severance Benefits (Details)

Severance Benefits (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Notes To Consolidated Financial Statements [Abstract]
Description Of Postemployment Benefits			Severance Benefits
Postemployment Benefits Period Expense	$ 1.2	$ 1.4	$ 1.6	$ 5.7
Postemployment Benefits Liability Current	$ 7.8		$ 7.8		$ 10.4

REGULATORY ACCOUNTING (Details)

REGULATORY ACCOUNTING (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Regulatory Asset [Line Items]
Regulatory Assets, Total	$ 4,726,400	$ 4,726,600
Regulatory Assets Current	709,660	672,493
Regulatory Assets Long Term	4,016,684	4,054,086
Regulatory Assets And Liabilities Other Disclosures Abstract
Amount of Regulatory Costs Not yet Approved	$ 60,800	60,500
Public Utilities Disclosure Of Regulatory Matters	2015 Regulatory Developments: FERC ROE Complaints: As a result of the March 3, 2015 FERC order in the pending ROE complaint proceedings described in Note 8C, "Commitments and Contingencies – FERC ROE Complaints," in 2015, Eversource recognized a pre-tax charge to earnings (excluding interest) of $20 million, of which $12.5 million was recorded at CL&P, $2.4 million at NSTAR Electric, $1 million at PSNH, and $4.1 million at WMECO. The pre-tax charge was recorded as a regulatory liability and as a reduction to Operating Revenues. NSTAR Electric and NSTAR Gas 2014 Comprehensive Settlement Agreement: On March 2, 2015, the DPU approved the comprehensive settlement agreement between NSTAR Electric, NSTAR Gas and the Massachusetts Attorney General (the "Settlement") as filed with the DPU on December 31, 2014. The Settlement resolved the outstanding NSTAR Electric CPSL program filings for 2006 through 2011, the NSTAR Electric and NSTAR Gas PAM and energy efficiency-related customer billing adjustments reported in 2012, and the recovery of LBR related to NSTAR Electric's energy efficiency programs for 2009 through 2011 (11 dockets in total). In 2015, as a result of the DPU order, NSTAR Electric and NSTAR Gas commenced refunding a combined $44.7 million to customers, which was recorded as a regulatory liability. NSTAR Electric recognized a $21.7 million pre-tax benefit in the first half of 2015 as a result of the approval of the Settlement. NSTAR Electric Basic Service Bad Debt Adder: On January 7, 2015, the DPU issued an order concluding that NSTAR Electric had removed energy-related bad debt costs from base distribution rates effective January 1, 2006. The DPU ordered NSTAR Electric and the Massachusetts Attorney General to collaborate on the reconciliations of energy-related bad debt costs through 2014. As a result of the DPU order, NSTAR Electric increased its regulatory assets and reduced operations and maintenance expense by $24.2 million in the first quarter, resulting in after-tax earnings of $14.5 million. On May 5, 2015, NSTAR Electric filed for recovery of the energy-related bad debt costs regulatory asset from customers beginning July 1, 2015. On June 24, 2015, the DPU delayed the effective date of NSTAR Electric’s proposed rate increase from July 1, 2015 to November 1, 2015 to allow for the DPU staff to review the reconciliations. The established procedural schedule is expected to result in an approval of the proposed rate increase in the fourth quarter of 2015. CL&P Distribution Rates: On December 17, 2014, PURA granted a re-opener request to CL&P’s base distribution rate application for further review of the appropriate balance of ADIT utilized in the calculation of rate base. On July 2, 2015, PURA issued a final order that approved a settlement agreement filed on May 19, 2015 between CL&P and the PURA Prosecutorial Staff. The order allows for an increase to rate base of approximately $166 million associated with ADIT, including a regulatory asset to recover the incremental revenue requirement for the period December 1, 2014 through November 30, 2015 over a subsequent two-year period. The rate base increase provided an increase to total allowed annual revenue requirements of $18.4 million beginning December 1, 2014. Of that amount, $10.7 million has been recorded as a regulatory asset in June 2015, with a corresponding increase in Operating Revenues. The remaining $7.7 million will be recorded from July 2015 through November 2015. The aggregate amount will be collected from customers in rates over a 24-month period commencing on December 1, 2015.
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	$ 719,300	750,100
Regulatory Liability Current	208,510	235,022
Regulatory Liabilities Long-Term	510,807	515,144
The Connecticut Light And Power Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	1,725,200	1,695,800
Regulatory Assets Current	263,713	220,344
Regulatory Assets Long Term	1,461,483	1,475,508
Regulatory Assets And Liabilities Other Disclosures Abstract
Amount of Regulatory Costs Not yet Approved	1,900	1,300
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	193,800	206,000
Regulatory Liability Current	122,617	124,722
Regulatory Liabilities Long-Term	71,245	81,298
NSTAR Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	1,456,700	1,377,800
Regulatory Assets Current	258,489	198,710
Regulatory Assets Long Term	1,198,167	1,179,100
Regulatory Assets And Liabilities Other Disclosures Abstract
Amount of Regulatory Costs Not yet Approved	21,900	33,200
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	271,600	312,300
Regulatory Liability Current	5,007	49,611
Regulatory Liabilities Long-Term	266,572	262,738
Public Service Company Of New Hampshire [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	371,000	404,800
Regulatory Assets Current	88,773	111,705
Regulatory Assets Long Term	282,215	293,115
Regulatory Assets And Liabilities Other Disclosures Abstract
Amount of Regulatory Costs Not yet Approved	2,000	900
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	55,900	67,400
Regulatory Liability Current	5,602	16,044
Regulatory Liabilities Long-Term	50,250	51,372
Western Massachusetts Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	193,000	198,200
Regulatory Assets Current	54,926	51,923
Regulatory Assets Long Term	138,138	146,307
Regulatory Assets And Liabilities Other Disclosures Abstract
Amount of Regulatory Costs Not yet Approved	15,400	11,000
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	29,700	33,300
Regulatory Liability Current	16,847	22,486
Regulatory Liabilities Long-Term	12,921	10,835
Cost Of Removal [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	434,900	439,900
Cost Of Removal [Member] | The Connecticut Light And Power Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	13,500	19,700
Cost Of Removal [Member] | NSTAR Electric Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	261,500	258,300
Cost Of Removal [Member] | Public Service Company Of New Hampshire [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	49,100	50,300
Cost Of Removal [Member] | Western Massachusetts Electric Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	2,800	1,100
Regulatory Tracker Deferrals Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	198,000	192,300
Regulatory Tracker Deferrals Regulatory Liabilities [Member] | The Connecticut Light And Power Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	115,600	122,600
Regulatory Tracker Deferrals Regulatory Liabilities [Member] | NSTAR Electric Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	2,900	20,700
Regulatory Tracker Deferrals Regulatory Liabilities [Member] | Public Service Company Of New Hampshire [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	4,800	14,200
Regulatory Tracker Deferrals Regulatory Liabilities [Member] | Western Massachusetts Electric Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	17,000	22,300
AFUDC Transmission Incentive [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	66,200	67,100
AFUDC Transmission Incentive [Member] | The Connecticut Light And Power Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	52,200	53,600
AFUDC Transmission Incentive [Member] | NSTAR Electric Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	5,000	4,400
AFUDC Transmission Incentive [Member] | Western Massachusetts Electric Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	9,000	9,100
Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	20,200	50,800
Other Regulatory Liabilities [Member] | The Connecticut Light And Power Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	12,500	10,100
Other Regulatory Liabilities [Member] | NSTAR Electric Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	2,200	28,900
Other Regulatory Liabilities [Member] | Public Service Company Of New Hampshire [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	2,000	2,900
Other Regulatory Liabilities [Member] | Western Massachusetts Electric Company [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities, Total	900	800
Benefit Costs [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	1,980,000	2,016,000
Benefit Costs [Member] | The Connecticut Light And Power Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	443,300	445,400
Benefit Costs [Member] | NSTAR Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	496,100	515,900
Benefit Costs [Member] | Public Service Company Of New Hampshire [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	175,100	174,300
Benefit Costs [Member] | Western Massachusetts Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	85,900	85,000
Regulatory Assets Offsetting Derivative Liabilities [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	423,700	425,500
Regulatory Assets Offsetting Derivative Liabilities [Member] | The Connecticut Light And Power Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	420,200	410,900
Regulatory Assets Offsetting Derivative Liabilities [Member] | NSTAR Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	2,200	4,500
Regulatory Assets Offsetting Derivative Liabilities [Member] | Public Service Company Of New Hampshire [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	0	0
Regulatory Assets Offsetting Derivative Liabilities [Member] | Western Massachusetts Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	0	0
Deferred Income Tax Charges Member
Regulatory Asset [Line Items]
Regulatory Assets, Total	631,500	635,300
Deferred Income Tax Charges Member | The Connecticut Light And Power Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	438,900	437,700
Deferred Income Tax Charges Member | NSTAR Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	84,000	83,700
Deferred Income Tax Charges Member | Public Service Company Of New Hampshire [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	34,800	38,000
Deferred Income Tax Charges Member | Western Massachusetts Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	30,700	35,500
Storm Restoration Costs [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	484,300	502,800
Storm Restoration Costs [Member] | The Connecticut Light And Power Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	298,400	319,600
Storm Restoration Costs [Member] | NSTAR Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	117,100	103,700
Storm Restoration Costs [Member] | Public Service Company Of New Hampshire [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	41,100	47,700
Storm Restoration Costs [Member] | Western Massachusetts Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	27,700	31,800
Goodwill Regulatory Asset [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	495,100	505,400
Goodwill Regulatory Asset [Member] | NSTAR Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	425,100	433,900
Regulatory Tracker Deferrals Regulatory Assets [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	430,700	350,500
Regulatory Tracker Deferrals Regulatory Assets [Member] | The Connecticut Light And Power Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	44,800	16,100
Regulatory Tracker Deferrals Regulatory Assets [Member] | NSTAR Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	255,000	141,400
Regulatory Tracker Deferrals Regulatory Assets [Member] | Public Service Company Of New Hampshire [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	84,300	103,500
Regulatory Tracker Deferrals Regulatory Assets [Member] | Western Massachusetts Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	36,000	33,000
Unrecovered Contractual Obligations [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	124,800	123,800
Other Regulatory Assets [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	156,300	167,300
Other Regulatory Assets [Member] | The Connecticut Light And Power Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	79,600	66,100
Other Regulatory Assets [Member] | NSTAR Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	77,200	94,700
Other Regulatory Assets [Member] | Public Service Company Of New Hampshire [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	35,700	41,300
Other Regulatory Assets [Member] | Western Massachusetts Electric Company [Member]
Regulatory Asset [Line Items]
Regulatory Assets, Total	$ 12,700	$ 12,900

PROPERTY, PLANT AND ACCUMULAT42

PROPERTY, PLANT AND ACCUMULATED DEPRECIATION (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Public Utility Property Plant And Equipment [Line Items]
Public Utilities Property Plant And Equipment Distribution	$ 12,701,600	$ 12,495,200
Public Utilities Property Plant And Equipment Distribution Natural Gas	2,625,900	2,595,400
Public Utilities Property Plant And Equipment Transmission	7,196,300	6,930,700
Public Utilities Property Plant And Equipment Generation Or Processing	1,175,900	1,170,900
Public Utilities Property Plant And Equipment Electric And Natural Gas Utility Total	23,699,700	23,192,200
Public Utilities Property Plant And Equipment Other Property Plant And Equipment	547,500	551,300
Public Utilities Property Plant And Equipment Plant In Service	24,247,200	23,743,500
Less Accumulated Depreciation [Abstract]
Electric And Natural Gas Utility Accumulated Depreciation	(5,950,400)	(5,777,800)
Other Accumulated Depreciation	(238,400)	(231,800)
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation	(6,188,800)	(6,009,600)
Property Plant And Equipment Net Excluding Construction Work In Progress	18,058,400	17,733,900
Public Utilities Property Plant And Equipment Construction Work In Progress	1,020,800	913,100
Property, Plant and Equipment, Net	19,079,189	18,647,041
The Connecticut Light And Power Company [Member]
Public Utility Property Plant And Equipment [Line Items]
Public Utilities Property Plant And Equipment Distribution	5,245,300	5,158,800
Public Utilities Property Plant And Equipment Transmission	3,455,500	3,274,000
Public Utilities Property Plant And Equipment Generation Or Processing	0	0
Public Utilities Property Plant And Equipment Plant In Service	8,700,800	8,432,800
Less Accumulated Depreciation [Abstract]
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation	(1,975,900)	(1,928,000)
Property Plant And Equipment Net Excluding Construction Work In Progress	6,724,900	6,504,800
Public Utilities Property Plant And Equipment Construction Work In Progress	209,700	304,900
Property, Plant and Equipment, Net	6,934,618	6,809,664
NSTAR Electric Company [Member]
Public Utility Property Plant And Equipment [Line Items]
Public Utilities Property Plant And Equipment Distribution	4,954,700	4,895,500
Public Utilities Property Plant And Equipment Transmission	1,965,200	1,928,500
Public Utilities Property Plant And Equipment Generation Or Processing	0	0
Public Utilities Property Plant And Equipment Plant In Service	6,919,900	6,824,000
Less Accumulated Depreciation [Abstract]
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation	(1,824,900)	(1,761,400)
Property Plant And Equipment Net Excluding Construction Work In Progress	5,095,000	5,062,600
Public Utilities Property Plant And Equipment Construction Work In Progress	356,700	272,800
Property, Plant and Equipment, Net	5,451,668	5,335,436
Public Service Company Of New Hampshire [Member]
Public Utility Property Plant And Equipment [Line Items]
Public Utilities Property Plant And Equipment Distribution	1,744,800	1,696,700
Public Utilities Property Plant And Equipment Transmission	821,200	789,700
Public Utilities Property Plant And Equipment Generation Or Processing	1,141,500	1,136,500
Public Utilities Property Plant And Equipment Plant In Service	3,707,500	3,622,900
Less Accumulated Depreciation [Abstract]
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation	(1,127,600)	(1,090,000)
Property Plant And Equipment Net Excluding Construction Work In Progress	2,579,900	2,532,900
Public Utilities Property Plant And Equipment Construction Work In Progress	135,000	102,900
Property, Plant and Equipment, Net	2,714,915	2,635,844
Public Service Company Of New Hampshire [Member] | Generation Plant [Member]
Less Accumulated Depreciation [Abstract]
Electric And Natural Gas Utility Accumulated Depreciation	(505,600)
Western Massachusetts Electric Company [Member]
Public Utility Property Plant And Equipment [Line Items]
Public Utilities Property Plant And Equipment Distribution	796,800	784,200
Public Utilities Property Plant And Equipment Transmission	906,400	891,000
Public Utilities Property Plant And Equipment Generation Or Processing	34,400	34,400
Public Utilities Property Plant And Equipment Plant In Service	1,737,600	1,709,600
Less Accumulated Depreciation [Abstract]
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation	(309,200)	(297,400)
Property Plant And Equipment Net Excluding Construction Work In Progress	1,428,400	1,412,200
Public Utilities Property Plant And Equipment Construction Work In Progress	79,800	49,100
Property, Plant and Equipment, Net	$ 1,508,207	$ 1,461,321

DERIVATIVE INSTURMENTS (Details

DERIVATIVE INSTURMENTS (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015USD ($)$ / KWmo$ / MWh	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)$ / KWmo$ / MWh	Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)$ / KWmo$ / MWh$ / REC
Derivative Instrument Detail Abstract
Derivative Liabilities, Noncurrent	$ (380,966)		$ (380,966)		$ (409,632)
Other Derivatives Not Designated As Hedging Instruments At Fair Value Net Total Abstract
Description of Derivative Activity Volume			As required by regulation, CL&P, along with UI, has capacity-related contracts with generation facilities. CL&P has a sharing agreement with UI, with 80 percent of each contract allocated to CL&P and 20 percent allocated to UI. The combined capacity of these contracts is 787 MW. The capacity contracts extend through 2026 and obligate both CL&P and UI to make or receive payments on a monthly basis to or from the generation facilities based on the difference between a set capacity price and the capacity market price received in the ISO-NE capacity markets. In addition, CL&P has a contract to purchase 0.1 million MWh of energy per year through 2020. NSTAR Electric has a renewable energy contract to purchase 0.1 million MWh of energy per year through 2018 and a capacity-related contract to purchase up to 35 MW per year through 2019. As of June 30, 2015 and December 31, 2014, Eversource had NYMEX financial contracts for natural gas futures in order to reduce variability associated with the purchase price of approximately 6.8 million and 8.8 million MMBtu of natural gas, respectively.
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net Abstract
Derivative Instruments Gain Loss Recognized In Regulatory Asset Liability	(36,600)	$ 111,600	$ (50,100)	$ 166,000
Derivative Credit Risk Related Contingent Features Abstract
Derivative Net Liability Position Aggregate Fair Value	(1,300)		(1,300)		(10,000)
Collateral Already Posted Aggregate Fair Value	1,300		$ 1,300
Additional Collateral Aggregate Fair Value					10,000
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsExitPricePremium			Exit price premiums of 6 percent through 23 percent are also applied on these contracts and reflect the most recent market activity available for similar type contracts
The Connecticut Light And Power Company [Member]
Derivative Instrument Detail Abstract
Derivative Liabilities - Current	(90,933)		$ (90,933)		(88,459)
Derivative Liabilities, Noncurrent	$ (380,196)		$ (380,196)		(406,199)
Other Derivatives Not Designated As Hedging Instruments At Fair Value Net Total Abstract
Description of Derivative Activity Volume			As required by regulation, CL&P, along with UI, has capacity-related contracts with generation facilities. CL&P has a sharing agreement with UI, with 80 percent of each contract allocated to CL&P and 20 percent allocated to UI. The combined capacity of these contracts is 787 MW. The capacity contracts extend through 2026 and obligate both CL&P and UI to make or receive payments on a monthly basis to or from the generation facilities based on the difference between a set capacity price and the capacity market price received in the ISO-NE capacity markets. In addition, CL&P has a contract to purchase 0.1 million MWh of energy per year through 2020.
NSTAR Electric Company [Member]
Other Derivatives Not Designated As Hedging Instruments At Fair Value Net Total Abstract
Description of Derivative Activity Volume	NSTAR Electric has a renewable energy contract to purchase 0.1 million MWh of energy per year through 2018 and a capacity-related contract to purchase up to 35 MW per year through 2019.
Fair Value Inputs Level 2 [Member]
Derivative Instrument Detail Abstract
Derivative Liabilities - Current	$ (1,300)		$ (1,300)		(9,800)
Derivative Liabilities, Noncurrent	0		0		(300)
Fair Value Inputs Level 3 [Member]
Derivative Instrument Detail Abstract
Derivative Assets - Current	6,100		6,100		9,600
Derivative Liabilities - Current	(92,700)		(92,700)		(90,000)
Derivative Liabilities, Noncurrent	(381,000)		(381,000)		(409,300)
Derivative Assets Noncurrent	$ 45,200		$ 45,200		$ 74,300
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsEnergyPrices | $ / MWh	45		45		52
Fair Value Inputs Level 3 [Member] | MinimumMember
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsCapacityPrices | $ / KWmo	10.05		10.05		5.30
FairValueInputsRenewableEnergyCreditPrices | $ / KWmo	46		46		38
FairValueInputsForwardReserve | $ / KWmo	2.40		2.40		5.80
Fair Value Inputs Level 3 [Member] | MaximumMember
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsCapacityPrices | $ / KWmo	12.60		12.60		12.98
FairValueInputsRenewableEnergyCreditPrices	51		51		56
FairValueInputsForwardReserve | $ / KWmo					9.50
Fair Value Inputs Level 3 [Member] | The Connecticut Light And Power Company [Member]
Derivative Instrument Detail Abstract
Derivative Assets - Current	$ 6,100		$ 6,100		$ 9,500
Derivative Liabilities - Current	(90,900)		(90,900)		(88,500)
Derivative Liabilities, Noncurrent	(380,200)		(380,200)		(406,200)
Derivative Assets Noncurrent	$ 44,800		$ 44,800		$ 74,300
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsEnergyPrices | $ / MWh	45		45		52
Fair Value Inputs Level 3 [Member] | The Connecticut Light And Power Company [Member] | MinimumMember
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsCapacityPrices | $ / KWmo	10.81		10.81		11.08
FairValueInputsForwardReserve | $ / KWmo	2.40		2.40		5.80
Fair Value Inputs Level 3 [Member] | The Connecticut Light And Power Company [Member] | MaximumMember
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsCapacityPrices | $ / KWmo	12.60		12.60		12.98
FairValueInputsForwardReserve | $ / KWmo					9.50
Fair Value Inputs Level 3 [Member] | NSTAR Electric Company [Member]
Derivative Instrument Detail Abstract
Derivative Assets - Current					$ 100
Derivative Liabilities - Current	$ (1,800)		$ (1,800)		(1,500)
Derivative Liabilities, Noncurrent	(800)		(800)		$ (3,100)
Derivative Assets Noncurrent	$ 400		$ 400
Fair Value Inputs Level 3 [Member] | NSTAR Electric Company [Member] | MinimumMember
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsCapacityPrices | $ / KWmo	10.05		10.05		5.30
FairValueInputsRenewableEnergyCreditPrices	46		46		38
Fair Value Inputs Level 3 [Member] | NSTAR Electric Company [Member] | MaximumMember
FairValueInputsQuantitativeInformation[Abstract]
FairValueInputsCapacityPrices | $ / KWmo	10.81		10.81		11.10
FairValueInputsRenewableEnergyCreditPrices	51		51		56
Amount Offset Against Derivatives [Member] | Fair Value Inputs Level 2 [Member]
Derivative Instrument Detail Abstract
Derivative Liabilities - Current	$ 200		$ 200
Amount Offset Against Derivatives [Member] | Fair Value Inputs Level 3 [Member]
Derivative Instrument Detail Abstract
Derivative Assets - Current	(10,400)		(10,400)		$ (6,600)
Derivative Liabilities - Current	0		0
Derivative Assets Noncurrent	(23,900)		(23,900)		(19,200)
Amount Offset Against Derivatives [Member] | Fair Value Inputs Level 3 [Member] | The Connecticut Light And Power Company [Member]
Derivative Instrument Detail Abstract
Derivative Assets - Current	(10,400)		(10,400)		(6,600)
Derivative Assets Noncurrent	(23,900)		(23,900)		(19,200)
Commodity [Member] | Fair Value Inputs Level 2 [Member]
Derivative Instrument Detail Abstract
Derivative Liabilities - Current	(1,500)		(1,500)		(9,800)
Derivative Liabilities, Noncurrent	0		0		(300)
Commodity [Member] | Fair Value Inputs Level 3 [Member]
Derivative Instrument Detail Abstract
Derivative Assets - Current	16,500		16,500		16,200
Derivative Liabilities - Current	(92,700)		(92,700)		(90,000)
Derivative Liabilities, Noncurrent	(381,000)		(381,000)		(409,300)
Derivative Assets Noncurrent	69,100		69,100		93,500
Commodity [Member] | Fair Value Inputs Level 3 [Member] | The Connecticut Light And Power Company [Member]
Derivative Instrument Detail Abstract
Derivative Assets - Current	16,500		16,500		16,100
Derivative Liabilities - Current	(90,900)		(90,900)		(88,500)
Derivative Liabilities, Noncurrent	(380,200)		(380,200)		(406,200)
Derivative Assets Noncurrent	68,700		68,700		93,500
Commodity [Member] | Fair Value Inputs Level 3 [Member] | NSTAR Electric Company [Member]
Derivative Instrument Detail Abstract
Derivative Assets - Current					100
Derivative Liabilities - Current	(1,800)		(1,800)		(1,500)
Derivative Liabilities, Noncurrent	(800)		(800)		$ (3,100)
Derivative Assets Noncurrent	$ 400		$ 400

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ (406.8)	$ (564.3)	$ (415.4)	$ (635.2)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability	(37.1)	111.8	(49.2)	161.3
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	21.5	21.6	42.2	43
Ending Balance	(422.4)	(430.9)	(422.4)	(430.9)
The Connecticut Light And Power Company [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	(403.3)	(557)	(410.9)	(630.6)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability	(36.8)	112.2	(48.9)	164.5
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	19.9	20.2	39.6	41.5
Ending Balance	(420.2)	(424.6)	(420.2)	(424.6)
NSTAR Electric Company [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	(3.5)	(7.3)	(4.5)	(7.3)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability	(0.3)	(0.4)	(0.3)	(0.5)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	1.6	1.4	2.6	1.5
Ending Balance	$ (2.2)	$ (6.3)	$ (2.2)	$ (6.3)

MARKETABLE SECURITIES (Details)

MARKETABLE SECURITIES (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Marketable Securities, Restricted	$ 450		$ 450		$ 450.8
Available For Sale Securities Debt Maturities Fair Value Abstract
Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value	61.2		61.2
Available For Sale Securities Debt Maturities After Ten Years Fair Value	121.5		121.5
Available For Sale Securities Debt Maturities After One Year Through Five Years Fair Value	70.8		70.8
Available For Sale Securities Debt Maturities Within One Year Fair Value	66.1		66.1
Available For Sale Securities Debt Maturities Fair Value	319.6		319.6
Available For Sale Securities Debt Maturities Amortized Cost Abstract
Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost	70.4		70.4
Available For Sale Securities Debt Maturities Within One Year Amortized Cost	66.1		66.1
Available For Sale Securities Debt Maturities After Ten Years Amortized Cost	118.7		118.7
Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost	60.1		60.1
Available For Sale Securities Debt Maturities Amortized Cost	315.3		315.3
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	622.7		622.7		639.2
TradingSecuritiesEquity	14.9		14.9		85.1
IncreaseDecreaseInTradingSecurities	0.5	$ 3.1	2.1	$ 3.8
Western Massachusetts Electric Company [Member]
Available For Sale Securities Debt Maturities Fair Value Abstract
Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value	0.6		0.6
Available For Sale Securities Debt Maturities After Ten Years Fair Value	3.1		3.1
Available For Sale Securities Debt Maturities After One Year Through Five Years Fair Value	16.2		16.2
Available For Sale Securities Debt Maturities Within One Year Fair Value	38.4		38.4
Available For Sale Securities Debt Maturities Fair Value	58.3		58.3
Available For Sale Securities Debt Maturities Amortized Cost Abstract
Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost	16.2		16.2
Available For Sale Securities Debt Maturities Within One Year Amortized Cost	38.4		38.4
Available For Sale Securities Debt Maturities After Ten Years Amortized Cost	3.1		3.1
Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost	0.6		0.6
Available For Sale Securities Debt Maturities Amortized Cost	58.3		58.3
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	58.3		58.3		58.1
Fair Value Inputs Level 1 Member
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	329.5		329.5		343.9
Fair Value Inputs Level 1 Member | Western Massachusetts Electric Company [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	2.1		2.1		4.3
Fair Value Inputs Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	293.2		293.2		295.3
Fair Value Inputs Level 2 [Member] | Western Massachusetts Electric Company [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	56.2		56.2		53.8
US Government Debt Securities Member | Fair Value Inputs Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	38.6		38.6		51.3
US Government Debt Securities Member | Fair Value Inputs Level 2 [Member] | Western Massachusetts Electric Company [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	0		0		0
Corporate Bond Securities Member | Fair Value Inputs Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	60.1		60.1		49.1
Corporate Bond Securities Member | Fair Value Inputs Level 2 [Member] | Western Massachusetts Electric Company [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	13.6		13.6		14.7
Asset Backed Securities Member | Fair Value Inputs Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	32		32		54.1
Asset Backed Securities Member | Fair Value Inputs Level 2 [Member] | Western Massachusetts Electric Company [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	10		10		14.5
Municipal Bonds Member | Fair Value Inputs Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	126.9		126.9		116.3
Municipal Bonds Member | Fair Value Inputs Level 2 [Member] | Western Massachusetts Electric Company [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	10.8		10.8		13
Other Debt Securities Member | Fair Value Inputs Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	35.6		35.6		24.5
Other Debt Securities Member | Fair Value Inputs Level 2 [Member] | Western Massachusetts Electric Company [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	21.8		21.8		11.6
Cash And Cash Equivalents Member | Fair Value Inputs Level 1 Member
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	26.4		26.4		24.9
Cash And Cash Equivalents Member | Fair Value Inputs Level 1 Member | Western Massachusetts Electric Company [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	2.1		2.1		4.3
Mutual Funds [Member] | Fair Value Inputs Level 1 Member
Fair Value Assets And Liabilities Measured On Recurring Basis Abstract
Investments Fair Value Disclosure	303.1		303.1		319
Debt Securities
Investments, Debt and Equity Securities [Abstract]
Available For Sale Securities Fair Value Disclosure	319.6		319.6		320.2
Available-for-sale Securities, Gross Unrealized Gains	4.9				7.5
AvailableForSaleSecuritiesGrossUnrealizedLoss	(0.6)				(0.3)
Available For Sale Securities Amortized Cost	315.3		315.3		313
Debt Securities | Western Massachusetts Electric Company [Member]
Investments, Debt and Equity Securities [Abstract]
Available For Sale Securities Fair Value Disclosure	58.3		58.3		58.1
Available-for-sale Securities, Gross Unrealized Gains	0				0
AvailableForSaleSecuritiesGrossUnrealizedLoss	0				(0.1)
Available For Sale Securities Amortized Cost	58.3		58.3		58.2
Equity Securities
Investments, Debt and Equity Securities [Abstract]
Available For Sale Securities Fair Value Disclosure	288.2		288.2		233.9
Available-for-sale Securities, Gross Unrealized Gains	72.9				73.3
AvailableForSaleSecuritiesGrossUnrealizedLoss	(1.2)				0
Available For Sale Securities Amortized Cost	$ 216.5		$ 216.5		$ 160.6

SHORT AND LONG-TERM TERM DEBT (

SHORT AND LONG-TERM TERM DEBT (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Line of Credit Facility, Description	Credit Agreements and Commercial Paper Programs: Eversource parent, CL&P, PSNH, WMECO, NSTAR Gas and Yankee Gas are parties to a five-year $1.45 billion revolving credit facility that expires September 6, 2019. The facility serves to backstop Eversource parent's $1.45 billion commercial paper program. The commercial paper program allows Eversource parent to issue commercial paper as a form of short-term debt. As of June 30, 2015 and December 31, 2014, Eversource parent had $576.5 million and approximately $1.1 billion, respectively, in short-term borrowings outstanding under the Eversource parent commercial paper program, leaving $873.5 million and $348.9 million of available borrowing capacity as of June 30, 2015 and December 31, 2014, respectively. The weighted-average interest rate on these borrowings as of June 30, 2015 and December 31, 2014 was 0.40 percent and 0.43 percent, respectively. As of June 30, 2015, there were intercompany loans from Eversource parent of $85.6 million to CL&P, $133.5 million to PSNH and $60.6 million to WMECO. As of December 31, 2014, there were intercompany loans from Eversource parent of $133.4 million to CL&P, $90.5 million to PSNH and $21.4 million to WMECO. NSTAR Electric has a five-year $450 million revolving credit facility that expires September 6, 2019. The facility serves to backstop NSTAR Electric's $450 million commercial paper program. As of June 30, 2015 and December 31, 2014, NSTAR Electric had $377.2 million and $302 million, respectively, in short-term borrowings outstanding under its commercial paper program, leaving $72.8 million and $148 million of available borrowing capacity as of June 30, 2015 and December 31, 2014, respectively. The weighted-average interest rate on these borrowings as of June 30, 2015 and December 31, 2014 was 0.19 percent and 0.27 percent, respectively.
Notes Payable	$ 953,700	$ 956,825
Long-term Debt, Description	Long-Term Debt: On January 15, 2015, Eversource parent issued $150 million of 1.60 percent Series G Senior Notes, due to mature in 2018 and $300 million of 3.15 percent Series H Senior Notes, due to mature in 2025. The proceeds, net of issuance costs, were used to repay short-term borrowings outstanding under the Eversource parent commercial paper program. As the debt issuances refinanced short-term debt, the short-term debt was classified as Long-Term Debt as of December 31, 2014. On April 1, 2015, CL&P repaid at maturity the $100 million 5.00 percent 2005 Series A First and Refunding Mortgage Bonds using short-term borrowings. On April 1, 2015, CL&P also redeemed the $62 million 1996A Series 1.55 percent PCRBs that were subject to mandatory tender, using short term borrowings. On May 20, 2015, CL&P issued $300 million of 4.15 percent 2015 Series A First and Refunding Mortgage Bonds due to mature in 2045. The proceeds, net of issuance costs, were used to repay short-term borrowings. On August 1, 2015, WMECO repaid at maturity the $50 million 5.24 percent Series C Senior Notes using short-term borrowings. Long-Term Debt Issuance Authorization: On April 3, 2015, the DPU authorized NSTAR Gas to issue up to $100 million in long-term debt for the period through December 31, 2015. On January 15, 2015, Eversource parent issued $150 million of 1.60 percent Series G Senior Notes, due to mature in 2018 and $300 million of 3.15 percent Series H Senior Notes, due to mature in 2025. The proceeds, net of issuance costs, were used to repay short-term borrowings outstanding under the Eversource parent commercial paper program. As the debt issuances refinanced short-term debt, the short-term debt was classified as Long-Term Debt as of December 31, 2014. On April 1, 2015, CL&P repaid at maturity the $100 million 5.00 percent 2005 Series A First and Refunding Mortgage Bonds using short-term borrowings. On April 1, 2015, CL&P also redeemed the $62 million 1996A Series 1.55 percent PCRBs that were subject to mandatory tender, using short term borrowings. On May 20, 2015, CL&P issued $300 million of 4.15 percent 2015 Series A First and Refunding Mortgage Bonds due to mature in 2045. The proceeds, net of issuance costs, were used to repay short-term borrowings. On August 1, 2015, WMECO repaid at maturity the $50 million 5.24 percent Series C Senior Notes using short-term borrowings.
The Connecticut Light And Power Company [Member]
Line of Credit Facility [Line Items]
Notes Payable To Affiliated Companies	$ 85,600	133,400
Long-term Debt, Description	On April 1, 2015, CL&P repaid at maturity the $100 million 5.00 percent 2005 Series A First and Refunding Mortgage Bonds using short-term borrowings. On April 1, 2015, CL&P also redeemed the $62 million 1996A Series 1.55 percent PCRBs that were subject to mandatory tender, using short term borrowings. On April 1, 2015, CL&P repaid at maturity the $100 million 5.00 percent 2005 Series A First and Refunding Mortgage Bonds using short-term borrowings. On April 1, 2015, CL&P also redeemed the $62 million 1996A Series 1.55 percent PCRBs that were subject to mandatory tender, using short term borrowings. On May 20, 2015, CL&P issued $300 million of 4.15 percent 2015 Series A First and Refunding Mortgage Bonds due to mature in 2045. The proceeds, net of issuance costs, were used to repay short-term borrowings.
NSTAR Electric Company [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 450,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 72,800	$ 148,000
Short-term Debt, Weighted Average Interest Rate	0.19%	0.27%
CommercialPaper	$ 377,200	$ 302,000
Notes Payable	377,200	302,000
Public Service Company Of New Hampshire [Member]
Line of Credit Facility [Line Items]
Notes Payable To Affiliated Companies	133,500	90,500
Western Massachusetts Electric Company [Member]
Line of Credit Facility [Line Items]
Notes Payable To Affiliated Companies	$ 60,600	21,400
Long-term Debt, Description	On August 1, 2015, WMECO repaid at maturity the $50 million 5.24 percent Series C Senior Notes using short-term borrowings.
Eversource Parent [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,450,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 873,500	$ 348,900
Short-term Debt, Weighted Average Interest Rate	0.40%	0.43%
CommercialPaper	$ 576,500	$ 1,100,000

PENSION BENEFITS AND POSTRETI47

PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSIONS (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Accrued Pension, SERP and PBOP	$ 1,636,769		$ 1,636,769		$ 1,638,558
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
Amount That Represents Deferred Regulatory Assets	800		1,600
Pension Plans Defined Benefit Member
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	22,800	$ 19,100	45,900	$ 41,500
Defined Benefit Plan Interest Cost	56,900	56,300	113,300	113,000
Defined Benefit Plan, Expected Return on Plan Assets	(83,900)	(77,700)	(168,200)	(155,400)
Defined Benefit Plan, Amortization of Gains (Losses)	36,500	31,700	75,500	64,700
Defined Benefit Plan Amortization Of Prior Service Cost Credit	900	1,100	1,800	2,100
Defined Benefit Plan Net Periodic Benefit Cost	33,200	30,500	68,300	65,900
Amount Capitalized Defined Benefit Expense	9,800	8,700	21,100	18,400
PBOP Plan
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	3,900	3,200	8,100	6,300
Defined Benefit Plan Interest Cost	11,700	12,100	23,600	24,700
Defined Benefit Plan, Expected Return on Plan Assets	(16,900)	(15,800)	(33,700)	(31,600)
Defined Benefit Plan, Amortization of Gains (Losses)	1,700	3,000	3,400	6,000
Defined Benefit Plan Amortization Of Prior Service Cost Credit	(200)	(700)	(200)	(1,400)
Defined Benefit Plan Net Periodic Benefit Cost	200	1,800	1,200	4,000
Amount Capitalized Defined Benefit Expense	(100)	400	0	800
The Connecticut Light And Power Company [Member]
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Accrued Pension, SERP and PBOP	286,131		286,131		273,854
The Connecticut Light And Power Company [Member] | Pension Plans Defined Benefit Member
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	6,200	5,000	12,200	10,200
Defined Benefit Plan Interest Cost	12,900	12,400	25,400	25,700
Defined Benefit Plan, Expected Return on Plan Assets	(19,800)	(18,700)	(39,400)	(38,000)
Defined Benefit Plan, Amortization of Gains (Losses)	8,000	8,200	16,200	17,300
Defined Benefit Plan Amortization Of Prior Service Cost Credit	400	500	800	900
Defined Benefit Plan Net Periodic Benefit Cost	7,700	7,400	15,200	16,100
Related Intercompany Allocationsof Defined Benefit Expense	5,800	7,500	12,200	14,300
Amount Capitalized Defined Benefit Expense	4,700	4,400	9,400	9,300
The Connecticut Light And Power Company [Member] | PBOP Plan
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	500	500	1,100	1,100
Defined Benefit Plan Interest Cost	1,800	1,900	3,500	4,000
Defined Benefit Plan, Expected Return on Plan Assets	(2,800)	(2,500)	(5,500)	(5,200)
Defined Benefit Plan, Amortization of Gains (Losses)	200	1,000	300	2,100
Defined Benefit Plan Amortization Of Prior Service Cost Credit			0	0
Defined Benefit Plan Net Periodic Benefit Cost	(300)	900	(600)	2,000
Related Intercompany Allocationsof Defined Benefit Expense	400	1,100	900	2,200
Amount Capitalized Defined Benefit Expense	(100)	500	(100)	1,000
NSTAR Electric Company [Member]
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Accrued Pension, SERP and PBOP	220,000		220,000		235,529
NSTAR Electric Company [Member] | Pension Plans Defined Benefit Member
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	3,700	3,000	7,500	7,600
Defined Benefit Plan Interest Cost	10,000	10,300	20,100	20,600
Defined Benefit Plan, Expected Return on Plan Assets	(17,500)	(15,700)	(35,100)	(31,500)
Defined Benefit Plan, Amortization of Gains (Losses)	8,700	5,900	18,400	11,700
Defined Benefit Plan Amortization Of Prior Service Cost Credit	0	0	0	0
Defined Benefit Plan Net Periodic Benefit Cost	4,900	3,500	10,900	8,400
Related Intercompany Allocationsof Defined Benefit Expense	3,400	1,400	6,900	3,800
Amount Capitalized Defined Benefit Expense	2,700	1,000	5,900	2,900
NSTAR Electric Company [Member] | PBOP Plan
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	1,300	800	2,700	1,600
Defined Benefit Plan Interest Cost	4,700	4,800	9,500	9,700
Defined Benefit Plan, Expected Return on Plan Assets	(6,900)	(6,500)	(13,700)	(13,000)
Defined Benefit Plan, Amortization of Gains (Losses)	400	(200)	1,200	(300)
Defined Benefit Plan Amortization Of Prior Service Cost Credit	(100)	(500)	(100)	(900)
Defined Benefit Plan Net Periodic Benefit Cost	(600)	(1,600)	(400)	(2,900)
Related Intercompany Allocationsof Defined Benefit Expense	200	0	400	100
Amount Capitalized Defined Benefit Expense	(200)	(500)	(100)	(1,000)
Public Service Company Of New Hampshire [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Amortization Of Prior Service Cost Credit		0
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Accrued Pension, SERP and PBOP	99,318		99,318		93,243
Public Service Company Of New Hampshire [Member] | Pension Plans Defined Benefit Member
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	3,100	2,300	6,000	5,100
Defined Benefit Plan Interest Cost	6,100	5,800	12,100	12,300
Defined Benefit Plan, Expected Return on Plan Assets	(10,100)	(9,300)	(20,200)	(19,500)
Defined Benefit Plan, Amortization of Gains (Losses)	2,900	2,800	5,800	6,000
Defined Benefit Plan Amortization Of Prior Service Cost Credit	100	100	200	300
Defined Benefit Plan Net Periodic Benefit Cost	2,100	1,700	3,900	4,200
Related Intercompany Allocationsof Defined Benefit Expense	1,600	2,100	3,400	4,200
Amount Capitalized Defined Benefit Expense	900	800	1,700	1,700
Public Service Company Of New Hampshire [Member] | PBOP Plan
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	300	300	700	700
Defined Benefit Plan Interest Cost	1,000	1,000	1,900	2,100
Defined Benefit Plan, Expected Return on Plan Assets	(1,500)	(1,300)	(3,000)	(2,700)
Defined Benefit Plan, Amortization of Gains (Losses)	100	600	300	1,100
Defined Benefit Plan Amortization Of Prior Service Cost Credit			0	0
Defined Benefit Plan Net Periodic Benefit Cost	(100)	600	(100)	1,200
Related Intercompany Allocationsof Defined Benefit Expense	100	300	200	600
Amount Capitalized Defined Benefit Expense	0	200	100	400
Western Massachusetts Electric Company [Member]
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Accrued Pension, SERP and PBOP	19,530		19,530		$ 17,705
Western Massachusetts Electric Company [Member] | Pension Plans Defined Benefit Member
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	1,000	800	2,200	1,900
Defined Benefit Plan Interest Cost	2,600	2,500	5,200	5,200
Defined Benefit Plan, Expected Return on Plan Assets	(4,700)	(4,400)	(9,400)	(9,000)
Defined Benefit Plan, Amortization of Gains (Losses)	1,600	1,700	3,200	3,500
Defined Benefit Plan Amortization Of Prior Service Cost Credit	100	100	100	200
Defined Benefit Plan Net Periodic Benefit Cost	600	700	1,300	1,800
Related Intercompany Allocationsof Defined Benefit Expense	1,100	1,400	2,300	2,700
Amount Capitalized Defined Benefit Expense	500	600	1,000	1,400
Western Massachusetts Electric Company [Member] | PBOP Plan
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Service Cost	100	100	200	200
Defined Benefit Plan Interest Cost	300	400	800	800
Defined Benefit Plan, Expected Return on Plan Assets	(600)	(600)	(1,300)	(1,100)
Defined Benefit Plan, Amortization of Gains (Losses)	0	100	0	200
Defined Benefit Plan Amortization Of Prior Service Cost Credit			0	0
Defined Benefit Plan Net Periodic Benefit Cost	(200)	0	(300)
Related Intercompany Allocationsof Defined Benefit Expense	100	200	200	400
Amount Capitalized Defined Benefit Expense	$ 0	$ 0	$ (100)	$ 100

Environmental Matters (Details)

Environmental Matters (Details) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2015USD ($)	Dec. 31, 2014USD ($)
Site Contingency [Line Items]
Environmental Site Quantity	65	65
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning Balance	$ 43.3
Ending Balance	46.2	$ 43.3
MGP Site accrual [Member]
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning Balance	38.8
Ending Balance	$ 40	$ 38.8
The Connecticut Light And Power Company [Member]
Site Contingency [Line Items]
Environmental Site Quantity	15	16
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning Balance	$ 3.8
Ending Balance	$ 4.9	$ 3.8
NSTAR Electric Company [Member]
Site Contingency [Line Items]
Environmental Site Quantity	14	13
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning Balance	$ 1.1
Ending Balance	$ 2.3	$ 1.1
Public Service Company Of New Hampshire [Member]
Site Contingency [Line Items]
Environmental Site Quantity	12	13
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning Balance	$ 5.2
Ending Balance	$ 3.4	$ 5.2
Western Massachusetts Electric Company [Member]
Site Contingency [Line Items]
Environmental Site Quantity	4	4
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning Balance	$ 0.5
Ending Balance	$ 0.6	$ 0.5

Guarantees and Indemnificatio49

Guarantees and Indemnifications (Details) $ in Millions	Jun. 30, 2015USD ($)
Guarantee Of Financial Obligations Of Npt [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations Maximum Exposure	$ 25
Various Subsidiary Surety Bonds And Performance Guarantees Expiring Between 2015 And 2016 [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations Maximum Exposure	33.8
Guarantee Of Rocky River Reality And Nusco Lease Payments For Real Estate And Vehicles Expiring 2019 Through 2024 [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations Maximum Exposure	12.7
Guarantee To Purchaser Of Es Boulos Company And A Bonding Company Expiring In 2016 And 2020 [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations Maximum Exposure	$ 42.1

Other Contingencies (Details)

Other Contingencies (Details) - Jun. 30, 2015 - USD ($) $ in Millions	Total	Total
Loss Contingencies Line Items
Public Utilities Disclosure Of Regulatory Matters	2015 Regulatory Developments: FERC ROE Complaints: As a result of the March 3, 2015 FERC order in the pending ROE complaint proceedings described in Note 8C, "Commitments and Contingencies – FERC ROE Complaints," in 2015, Eversource recognized a pre-tax charge to earnings (excluding interest) of $20 million, of which $12.5 million was recorded at CL&P, $2.4 million at NSTAR Electric, $1 million at PSNH, and $4.1 million at WMECO. The pre-tax charge was recorded as a regulatory liability and as a reduction to Operating Revenues. NSTAR Electric and NSTAR Gas 2014 Comprehensive Settlement Agreement: On March 2, 2015, the DPU approved the comprehensive settlement agreement between NSTAR Electric, NSTAR Gas and the Massachusetts Attorney General (the "Settlement") as filed with the DPU on December 31, 2014. The Settlement resolved the outstanding NSTAR Electric CPSL program filings for 2006 through 2011, the NSTAR Electric and NSTAR Gas PAM and energy efficiency-related customer billing adjustments reported in 2012, and the recovery of LBR related to NSTAR Electric's energy efficiency programs for 2009 through 2011 (11 dockets in total). In 2015, as a result of the DPU order, NSTAR Electric and NSTAR Gas commenced refunding a combined $44.7 million to customers, which was recorded as a regulatory liability. NSTAR Electric recognized a $21.7 million pre-tax benefit in the first half of 2015 as a result of the approval of the Settlement. NSTAR Electric Basic Service Bad Debt Adder: On January 7, 2015, the DPU issued an order concluding that NSTAR Electric had removed energy-related bad debt costs from base distribution rates effective January 1, 2006. The DPU ordered NSTAR Electric and the Massachusetts Attorney General to collaborate on the reconciliations of energy-related bad debt costs through 2014. As a result of the DPU order, NSTAR Electric increased its regulatory assets and reduced operations and maintenance expense by $24.2 million in the first quarter, resulting in after-tax earnings of $14.5 million. On May 5, 2015, NSTAR Electric filed for recovery of the energy-related bad debt costs regulatory asset from customers beginning July 1, 2015. On June 24, 2015, the DPU delayed the effective date of NSTAR Electric’s proposed rate increase from July 1, 2015 to November 1, 2015 to allow for the DPU staff to review the reconciliations. The established procedural schedule is expected to result in an approval of the proposed rate increase in the fourth quarter of 2015. CL&P Distribution Rates: On December 17, 2014, PURA granted a re-opener request to CL&P’s base distribution rate application for further review of the appropriate balance of ADIT utilized in the calculation of rate base. On July 2, 2015, PURA issued a final order that approved a settlement agreement filed on May 19, 2015 between CL&P and the PURA Prosecutorial Staff. The order allows for an increase to rate base of approximately $166 million associated with ADIT, including a regulatory asset to recover the incremental revenue requirement for the period December 1, 2014 through November 30, 2015 over a subsequent two-year period. The rate base increase provided an increase to total allowed annual revenue requirements of $18.4 million beginning December 1, 2014. Of that amount, $10.7 million has been recorded as a regulatory asset in June 2015, with a corresponding increase in Operating Revenues. The remaining $7.7 million will be recorded from July 2015 through November 2015. The aggregate amount will be collected from customers in rates over a 24-month period commencing on December 1, 2015.
FERC ROE Reserve - Incentive - First and Second Complaint [Member]
Loss Contingencies Line Items
Loss Contingency Loss in Period		$ 20
FERC ROE Reserve - Incentive - First and Second Complaint [Member] | The Connecticut Light And Power Company [Member]
Loss Contingencies Line Items
Loss Contingency Loss in Period		12.5
FERC ROE Reserve - Incentive - First and Second Complaint [Member] | NSTAR Electric Company [Member]
Loss Contingencies Line Items
Loss Contingency Loss in Period		2.4
FERC ROE Reserve - Incentive - First and Second Complaint [Member] | Public Service Company Of New Hampshire [Member]
Loss Contingencies Line Items
Loss Contingency Loss in Period		1
FERC ROE Reserve - Incentive - First and Second Complaint [Member] | Western Massachusetts Electric Company [Member]
Loss Contingencies Line Items
Loss Contingency Loss in Period		$ 4.1

FAIR VALUE OF FINANCIAL INSTR51

FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	$ 155,568	$ 155,568
Carrying Reported Amount Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	155,600	155,600
Other Long Term Debt	8,968,500	8,851,600
Estimate Of Fair Value Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	154,800	153,600
Other Long Term Debt	9,329,900	9,451,200
The Connecticut Light And Power Company [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	116,200	116,200
The Connecticut Light And Power Company [Member] | Carrying Reported Amount Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	116,200	116,200
Other Long Term Debt	2,975,100	2,842,000
The Connecticut Light And Power Company [Member] | Estimate Of Fair Value Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	113,000	112,000
Other Long Term Debt	3,242,900	3,214,500
NSTAR Electric Company [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	43,000	43,000
NSTAR Electric Company [Member] | Carrying Reported Amount Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	43,000	43,000
Other Long Term Debt	1,792,700	1,797,400
NSTAR Electric Company [Member] | Estimate Of Fair Value Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	41,800	41,600
Other Long Term Debt	1,916,600	1,993,500
Public Service Company Of New Hampshire [Member] | Carrying Reported Amount Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other Long Term Debt	1,076,300	1,076,300
Public Service Company Of New Hampshire [Member] | Estimate Of Fair Value Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other Long Term Debt	1,133,000	1,137,900
Western Massachusetts Electric Company [Member] | Carrying Reported Amount Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other Long Term Debt	628,000	628,500
Western Massachusetts Electric Company [Member] | Estimate Of Fair Value Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other Long Term Debt	$ 658,000	$ 689,400

ACCUMULATED OTHER COMPREHENSI52

ACCUMULATED OTHER COMPREHENSIVE INCOME (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accumulated Other Comprehensive Income Loss Net Of Tax RollForward [Abstract]
AOCI Beginning Balance			$ (74,009)	$ (46,000)
Other Comprehensive Income Before Reclassifications, Net of Tax			(1,500)	1,700
Reclassification From OCI, Net Of Tax			3,500	2,800
Other Comprehensive Income (Loss), Net of Tax, Total	$ 381	$ 2,814	1,976	4,524
AOCI Ending Balance	(72,033)	(41,500)	(72,033)	(41,500)
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Abstract]
Total Interest Expense	(92,259)	(92,495)	(187,102)	(182,471)
Income Tax Expense	(123,268)	(77,774)	(276,494)	(219,319)
Net Income Attributable to Controlling Interests	207,507	127,367	460,761	363,324
The Connecticut Light And Power Company [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax RollForward [Abstract]
AOCI Beginning Balance			(931)
Other Comprehensive Income (Loss), Net of Tax, Total	68	118	183	237
AOCI Ending Balance	(748)		(748)
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Abstract]
Total Interest Expense	(36,124)	(37,470)	(72,748)	(71,713)
Income Tax Expense	(43,129)	(20,401)	(81,276)	(65,942)
Public Service Company Of New Hampshire [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax RollForward [Abstract]
AOCI Beginning Balance			(7,369)
Other Comprehensive Income (Loss), Net of Tax, Total	215	303	514	607
AOCI Ending Balance	(6,855)		(6,855)
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Abstract]
Total Interest Expense	(11,662)	(10,999)	(22,935)	(22,971)
Income Tax Expense	(15,701)	(14,897)	(35,977)	(34,597)
Western Massachusetts Electric Company [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax RollForward [Abstract]
AOCI Beginning Balance			(3,176)
Other Comprehensive Income (Loss), Net of Tax, Total	72	86	158	173
AOCI Ending Balance	(3,018)		(3,018)
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Abstract]
Total Interest Expense	(6,291)	(6,707)	(13,112)	(12,353)
Income Tax Expense	(9,693)	(4,548)	(18,807)	(16,106)
Qualified Cash Flow Hedging Instruments [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax RollForward [Abstract]
AOCI Beginning Balance			(12,400)	(14,400)
Reclassification From OCI, Net Of Tax			1,000	1,000
Other Comprehensive Income (Loss), Net of Tax, Total			1,000	1,000
AOCI Ending Balance	(11,400)	(13,400)	(11,400)	(13,400)
Unrealized Gains Losses on Available for Sale Securities [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax RollForward [Abstract]
AOCI Beginning Balance			700	400
Other Comprehensive Income Before Reclassifications, Net of Tax			(1,100)	500
Other Comprehensive Income (Loss), Net of Tax, Total			(1,100)	500
AOCI Ending Balance	(400)	900	(400)	900
Pension, SERP and PBOP Benefit Plans [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax RollForward [Abstract]
AOCI Beginning Balance			(62,300)	(32,000)
Other Comprehensive Income Before Reclassifications, Net of Tax			(400)	1,200
Reclassification From OCI, Net Of Tax			2,500	1,800
Other Comprehensive Income (Loss), Net of Tax, Total			2,100	3,000
AOCI Ending Balance	$ (60,200)	$ (29,000)	$ (60,200)	$ (29,000)

COMMON SHARES (Details)

COMMON SHARES (Details) - $ / shares	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Class Of Stock [Line Items]
Common Stock Par Or Stated Value Per Share	$ 5	$ 5
Common Stock Shares Authorized	380,000,000	380,000,000
Common Stock Shares Issued	333,833,308	333,359,172
Treasury Stock Shares	16,671,366	16,375,835
Common Stock, Shares, Outstanding	317,161,942	316,983,337
Treasury Stock Shares Acquired	532,521
The Connecticut Light And Power Company [Member]
Class Of Stock [Line Items]
Common Stock Par Or Stated Value Per Share	$ 10	$ 10
Common Stock Shares Authorized	24,500,000	24,500,000
Common Stock Shares Issued	6,035,205	6,035,205
NSTAR Electric Company [Member]
Class Of Stock [Line Items]
Common Stock Par Or Stated Value Per Share	$ 1	$ 1
Common Stock Shares Authorized	100,000,000	100,000,000
Common Stock Shares Issued	100	100
Public Service Company Of New Hampshire [Member]
Class Of Stock [Line Items]
Common Stock Par Or Stated Value Per Share	$ 1	$ 1
Common Stock Shares Authorized	100,000,000	100,000,000
Common Stock Shares Issued	301	301
Western Massachusetts Electric Company [Member]
Class Of Stock [Line Items]
Common Stock Par Or Stated Value Per Share	$ 25	$ 25
Common Stock Shares Authorized	1,072,471	1,072,471
Common Stock Shares Issued	434,653	434,653

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Notes To Consolidated Financial Statements [Abstract]
Net Income Attributable to Controlling Interests	$ 207,507	$ 127,367	$ 460,761	$ 363,324
Basic	317,613,166	315,950,510	317,352,004	315,742,511
Weighted Average Number Diluted Shares Outstanding Adjustment	946,402	1,162,291	1,173,374	1,259,950
Diluted	318,559,568	317,112,801	318,525,378	317,002,461
Earnings Per Share Basic And Diluted	$ 0.65	$ 0.40	$ 1.45	$ 1.15

SEGMENT INFORMATION (Details)

SEGMENT INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Operating Revenues	$ 1,817,061	$ 1,677,614	$ 4,330,491	$ 3,968,204
Operating Income	412,015	293,990	909,490	761,679
Total Interest Expense	(92,259)	(92,495)	(187,102)	(182,471)
Other Income/(Loss), Net	12,899	5,526	18,626	7,194
Income Tax Expense	(123,268)	(77,774)	(276,494)	(219,319)
Net Income	209,387	129,247	464,520	367,083
Net Income Attributable to Noncontrolling Interests	(1,880)	(1,880)	(3,759)	(3,759)
Net Income Attributable to Controlling Interests	207,507	127,367	460,761	363,324
Total Assets	29,879,939		29,879,939		$ 29,777,975
Investments in Property, Plant and Equipment			740,379	724,043
Electric Distribution Member
Segment Reporting Information [Line Items]
Operating Revenues	1,382,700	1,261,800	3,142,800	2,847,800
Depreciation And Amortization	(98,500)	(89,300)	(257,600)	(238,200)
Operating Expenses, Other	(1,052,100)	(991,500)	(2,395,000)	(2,202,400)
Operating Income	232,100	181,000	490,200	407,200
Total Interest Expense	(45,600)	(47,200)	(93,200)	(94,600)
Other Income/(Loss), Net	5,500	2,900	7,600	4,300
Net Income Attributable to Controlling Interests	120,900	83,400	251,400	195,600
Total Assets	17,872,900		17,872,900		17,563,400
Investments in Property, Plant and Equipment			319,800	335,600
Natural Gas Distribution [Member]
Segment Reporting Information [Line Items]
Operating Revenues	186,000	195,500	693,400	628,300
Depreciation And Amortization	(17,700)	(16,900)	(35,900)	(34,600)
Operating Expenses, Other	(150,200)	(166,500)	(538,700)	(487,900)
Operating Income	18,100	12,100	118,800	105,800
Total Interest Expense	(9,100)	(8,700)	(18,100)	(17,100)
Other Income/(Loss), Net	300	0	100	100
Net Income Attributable to Controlling Interests	5,300	2,000	61,000	54,100
Total Assets	2,933,400		2,933,400		3,030,900
Investments in Property, Plant and Equipment			67,500	68,600
Electric Transmission [Member]
Segment Reporting Information [Line Items]
Operating Revenues	267,800	206,900	516,800	458,900
Depreciation And Amortization	(39,700)	(37,000)	(80,100)	(74,000)
Operating Expenses, Other	(73,100)	(71,000)	(147,200)	(137,300)
Operating Income	155,000	98,900	289,500	247,600
Total Interest Expense	(26,300)	(28,800)	(53,900)	(54,300)
Other Income/(Loss), Net	5,100	2,700	8,100	4,200
Net Income Attributable to Controlling Interests	80,400	43,900	147,000	118,800
Total Assets	7,589,700		7,589,700		7,625,600
Investments in Property, Plant and Equipment			328,700	289,300
Other Segment [Member]
Segment Reporting Information [Line Items]
Operating Revenues	203,700	184,700	443,700	356,900
Depreciation And Amortization	(7,100)	(7,700)	(14,300)	(14,700)
Operating Expenses, Other	(190,700)	(174,900)	(419,900)	(340,300)
Operating Income	5,900	2,100	9,500	1,900
Total Interest Expense	(12,400)	(9,100)	(24,100)	(18,700)
Other Income/(Loss), Net	220,100	137,700	535,000	432,400
Net Income Attributable to Controlling Interests	217,000	133,300	529,900	424,900
Total Assets	12,455,700		12,455,700		12,682,500
Investments in Property, Plant and Equipment			24,400	30,500
Eliminations Segment [Member]
Segment Reporting Information [Line Items]
Operating Revenues	(223,100)	(171,300)	(466,200)	(323,700)
Depreciation And Amortization	500	2,300	1,000	4,100
Operating Expenses, Other	223,500	168,900	466,700	318,800
Operating Income	900	(100)	1,500	(800)
Total Interest Expense	1,100	1,300	2,200	2,200
Other Income/(Loss), Net	(218,100)	(137,800)	(532,200)	(433,800)
Net Income Attributable to Controlling Interests	(216,100)	(135,200)	(528,500)	(430,100)
Total Assets	(10,971,800)		(10,971,800)		(11,124,400)
Investments in Property, Plant and Equipment			0	0
Total [Member]
Segment Reporting Information [Line Items]
Operating Revenues	1,817,100	1,677,600	4,330,500	3,968,200
Depreciation And Amortization	(162,500)	(148,600)	(386,900)	(357,400)
Operating Expenses, Other	(1,242,600)	(1,235,000)	(3,034,100)	(2,849,100)
Operating Income	412,000	294,000	909,500	761,700
Total Interest Expense	(92,300)	(92,500)	(187,100)	(182,500)
Other Income/(Loss), Net	12,900	5,500	18,600	7,200
Net Income Attributable to Controlling Interests	207,500	$ 127,400	460,800	363,300
Total Assets	$ 29,879,900		29,879,900		$ 29,778,000
Investments in Property, Plant and Equipment			$ 740,400	$ 724,000