2.4.0.8100190 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTStruefalsefalse1false falsefalseFROM_Jan01_2013_TO_Jun30_2013http://www.sec.gov/CIK0000072741duration2013-01-01T00:00:002013-06-30T00:00:001true 1nu_NotesToConsolidatedFinancialStatementsAbstractnu_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Notes To Consolidated Financial Statements [Abstract]2false 2us-gaap_FairValueDisclosuresTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse009.       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, Long-Term Debt and Rate Reduction Bonds: 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 projections. The fair value of fixed-rate long-term debt securities and RRBs 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. Adjustable rate securities are assumed to have a fair value equal to their carrying value. 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:<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="5" style="width: 133px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:133px;">As of June 30, 2013</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td colspan="5" style="width: 133px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:133px;">As of December 31, 2012</td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="5" style="width: 133px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:133px;">NU</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td colspan="5" style="width: 133px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:133px;">NU</td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="2" style="width: 60px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:60px;">Carrying</td><td style="width: 13px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:13px;"> </td><td colspan="2" style="width: 60px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:60px;">Fair </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td colspan="2" style="width: 60px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:60px;">Carrying</td><td style="width: 13px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:13px;"> </td><td colspan="2" style="width: 60px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:60px;">Fair</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">(Millions of Dollars) </td><td colspan="2" style="width: 60px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:60px;">Amount</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td colspan="2" style="width: 60px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:60px;">Value</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td colspan="2" style="width: 60px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:60px;">Amount</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td colspan="2" style="width: 60px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:60px;">Value</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">Preferred Stock Not</td><td style="width: 13px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:47px;"> </td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;">Subject to Mandatory Redemption</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;">$</td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 155.6</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;">$</td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 154.3</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;">$</td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 155.6</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;">$</td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 152.2</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">Long-Term Debt</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 8,539.7</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 8,841.1</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 7,963.5</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 8,640.7</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">Rate Reduction Bonds</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> - </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> - </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 82.1</td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 13px; text-align:left;border-color:#000000;min-width:13px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 83.0</td></tr></table></div><div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="23" style="width: 520px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:520px;">As of June 30, 2013</td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="5" style="width: 124px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:124px;">CL&P</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="5" style="width: 122px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:122px;">NSTAR Electric</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="5" style="width: 122px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:122px;">PSNH</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="5" style="width: 122px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:122px;">WMECO</td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="2" style="width: 57px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:57px;">Carrying</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 57px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:57px;">Fair </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Carrying</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Fair</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Carrying</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Fair</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Carrying</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Fair</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">(Millions of Dollars) </td><td colspan="2" style="width: 57px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:57px;">Amount</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 57px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:57px;">Value</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Amount</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Value</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Amount</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Value</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Amount</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Value</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">Preferred Stock Not</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;">Subject to Mandatory Redemption</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 116.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 112.0</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 43.0</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 42.3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> - </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> - </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> - </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> - </td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">Long-Term Debt</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 2,865.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 3,115.1</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 1,801.0</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 1,904.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 889.1</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 949.1</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 604.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 627.5</td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:left;border-color:#000000;min-width:46px;"> </td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="23" style="width: 520px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:520px;">As of December 31, 2012</td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="5" style="width: 124px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:124px;">CL&P</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="5" style="width: 122px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:122px;">NSTAR Electric </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="5" style="width: 122px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:122px;">PSNH</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="5" style="width: 122px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:122px;">WMECO</td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;"> </td><td colspan="2" style="width: 57px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:57px;">Carrying</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 57px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:57px;">Fair </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Carrying</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Fair</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Carrying</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Fair</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Carrying</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:56px;">Fair</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">(Millions of Dollars) </td><td colspan="2" style="width: 57px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:57px;">Amount</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 57px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:57px;">Value</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Amount</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Value</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Amount</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Value</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Amount</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 56px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:56px;">Value</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">Preferred Stock Not</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:47px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:46px;"> </td></tr><tr style="height: 10px"><td style="width: 9px; text-align:left;border-color:#000000;min-width:9px;"> </td><td style="width: 172px; text-align:left;border-color:#000000;min-width:172px;">Subject to Mandatory Redemption</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 116.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 110.0</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 43.0</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 42.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> - </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> - </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> - </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> - </td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">Long-Term Debt</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 2,862.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> 3,295.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 1,602.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 1,818.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 997.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 1,088.0</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 605.3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 660.4</td></tr><tr style="height: 10px"><td colspan="2" style="width: 181px; text-align:left;border-color:#000000;min-width:181px;">Rate Reduction Bonds</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> - </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 47px; text-align:right;border-color:#000000;min-width:47px;"> - </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 43.5</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 43.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 29.3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 29.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 9.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 46px; text-align:right;border-color:#000000;min-width:46px;"> 9.5</td></tr></table></div>Derivative Instruments: Derivative instruments are carried at fair value. For further information, see Note 4, "Derivative Instruments," to the financial statements.  Other Financial Instruments: Investments in marketable securities are carried at fair value. For further information, see Note 1E, "Summary of Significant Accounting Policies - Fair Value Measurements," and 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.falsefalsefalsenonnum:textBlockItemTypenaThe entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15A -Subparagraph a-d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15C, 15D -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 3, 10, 14, 15 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32, 33, 34 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. 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