Environmental Matters (Tablels)

12 Months Ended

Dec. 31, 2011

Notes To Consolidated Financial Statements [Abstract]

Schedule Of Environmental Loss Contingencies By Site Text Block

(Millions of Dollars)	NU		CL&P		PSNH		WMECO
Balance as of December 31, 2009	$	26.0	$	2.7	$	5.3	$	0.4
Additions		18.2		0.5		8.9		0.1
Payments		(7.1)		(0.4)		(5.1)		(0.2)
Balance as of December 31, 2010		37.1		2.8		9.1		0.3
Additions		1.6		0.4		0.1		0.1
Payments		(7.0)		(0.3)		(2.6)		(0.1)
Balance as of December 31, 2011	$	31.7	$	2.9	$	6.6	$	0.3

	As of December 31, 2011						As of December 31, 2010
					Portion Related to						Portion Related to
			Reserve		MGP Sites				Reserve		MGP Sites
	Number of Sites		(in millions)		(in millions)		Number of Sites		(in millions)		(in millions)
NU		59	$	31.7	$	28.9		58	$	37.1	$	35.2
CL&P		18		2.9		1.5		17		2.8		1.5
PSNH		18		6.6		5.8		18		9.1		8.3
WMECO		10		0.3		0.1		9		0.3		0.1