ASSET RETIREMENT OBLIGATIONS (TABLE)

12 Months Ended

Dec. 31, 2015

Notes To Consolidated Financial Statements [Abstract]

Schedule of Change in Asset Retirement Obligation [Table Text Block]

Eversource			As of December 31,
(Millions of Dollars)			2015		2014
Balance as of Beginning of Year			$	426.3	$	424.9
Liabilities Incurred During the Year				6.6		1.3
Liabilities Settled During the Year				(18.2)		(19.5)
Accretion				26.5		25.1
Revisions in Estimated Cash Flows				(11.1)		(5.5)
Balance as of End of Year			$	430.1	$	426.3
	As of December 31,
	2015								2014
			NSTAR								NSTAR
(Millions of Dollars)	CL&P		Electric		PSNH		WMECO		CL&P		Electric		PSNH		WMECO
Balance as of Beginning of Year	$	35.3	$	34.3	$	20.6	$	5.9	$	35.0	$	32.8	$	19.5	$	4.5
Liabilities Incurred During the Year		-		6.2		0.4		-		-		-		-		1.1
Liabilities Settled During the Year		-		(1.5)		-		(0.1)		(1.1)		-		-		-
Accretion		2.2		1.8		1.3		0.4		1.9		1.5		1.1		0.3
Revisions in Estimated Cash Flows		(3.7)		(5.5)		(0.7)		(0.5)		(0.5)		-		-		-
Balance as of End of Year	$	33.8	$	35.3	$	21.6	$	5.7	$	35.3	$	34.3	$	20.6	$	5.9