PROPERTY, PLANT AND ACCUMULATED DEPRECIATION (Tables)

3 Months Ended

Mar. 31, 2016

Notes To Consolidated Financial Statements [Abstract]

Schedule of Public Utility Property, Plant, and Equipment [Text Block]

		As of March 31, 2016		As of December 31, 2015
(Millions of Dollars)		Eversource		Eversource
Distribution - Electric		$	13,227.4	$	13,054.8
Distribution - Natural Gas			2,759.1		2,727.2
Transmission - Electric			7,725.3		7,691.9
Generation			1,210.3		1,194.1
Electric and Natural Gas Utility			24,922.1		24,668.0
Other (1)			575.5		558.6
Property, Plant and Equipment, Gross			25,497.6		25,226.6
Less: Accumulated Depreciation
	Electric and Natural Gas Utility		(6,249.0)		(6,141.1)
	Other		(264.8)		(255.6)
Total Accumulated Depreciation			(6,513.8)		(6,396.7)
Property, Plant and Equipment, Net			18,983.8		18,829.9
Construction Work in Progress			1,112.9		1,062.5
Total Property, Plant and Equipment, Net		$	20,096.7	$	19,892.4

	As of March 31, 2016								As of December 31, 2015
			NSTAR								NSTAR
(Millions of Dollars)	CL&P		Electric		PSNH		WMECO		CL&P		Electric		PSNH		WMECO
Distribution	$	5,429.5	$	5,176.1	$	1,839.5	$	822.2	$	5,377.2	$	5,100.5	$	1,804.8	$	812.3
Transmission		3,631.3		2,137.7		936.1		971.0		3,618.0		2,131.3		928.2		964.9
Generation		-		-		1,174.3		36.0		-		-		1,158.1		36.0
Property, Plant and Equipment, Gross		9,060.8		7,313.8		3,949.9		1,829.2		8,995.2		7,231.8		3,891.1		1,813.2
Less: Accumulated Depreciation		(2,073.7)		(1,924.4)		(1,192.0)		(317.0)		(2,041.9)		(1,886.8)		(1,171.0)		(307.0)
Property, Plant and Equipment, Net		6,987.1		5,389.4		2,757.9		1,512.2		6,953.3		5,345.0		2,720.1		1,506.2
Construction Work in Progress		244.1		310.7		123.5		78.3		203.5		310.5		135.3		69.1
Total Property, Plant and Equipment, Net	$	7,231.2	$	5,700.1	$	2,881.4	$	1,590.5	$	7,156.8	$	5,655.5	$	2,855.4	$	1,575.3