Dividend Restrictions	12 Months Ended
Dec. 31, 2011
Notes To Consolidated Financial Statements [Abstract]
Schedule of Dividend Payment Restrictions [Table Text Block]	17. DIVIDEND RESTRICTIONS NU parent's ability to pay dividends may be affected by certain state statutes, the ability of its subsidiaries to pay common dividends and the leverage restriction tied to its consolidated total debt to total capitalization ratio requirement in its revolving credit agreement. CL&P, PSNH and WMECO are subject to Section 305 of the Federal Power Act that makes it unlawful for a public utility to make or pay a dividend from any funds "properly included in its capital account." Management believes that this Federal Power Act restriction, as applied to CL&P, PSNH and WMECO, would not be construed or applied by the FERC to prohibit the payment of dividends for lawful and legitimate business purposes from retained earnings. In addition, certain state statutes may impose additional limitations on such companies and on Yankee Gas. Such state law restrictions do not restrict payment of dividends from retained earnings or net income. CL&P, PSNH, WMECO and Yankee Gas also have a revolving credit agreement that imposes leverage restrictions including consolidated total debt to total capitalization ratio requirements. The Retained Earnings balances subject to these leverage restrictions are $1.652 billion for NU, $735.9 million for CL&P, $388.9 million for PSNH and $115.5 million for WMECO as of December 31, 2011. PSNH is further required to reserve an additional amount under its FERC hydroelectric license conditions. As of December 31, 2011, approximately $11.9 million of PSNH's Retained Earnings is subject to restriction under its FERC hydroelectric license conditions. . As of December 31, 2011, NU, CL&P, PSNH, WMECO and Yankee Gas were in compliance with all such provisions of its credit agreement that may restrict the payment of dividends

Dividend Restrictions

12 Months Ended

Dec. 31, 2011

Notes To Consolidated Financial Statements [Abstract]

Schedule of Dividend Payment Restrictions [Table Text Block]

17. DIVIDEND RESTRICTIONS

NU parent's ability to pay dividends may be affected by certain state statutes, the ability of its subsidiaries to pay common dividends and the leverage restriction tied to its consolidated total debt to total capitalization ratio requirement in its revolving credit agreement.

CL&P, PSNH and WMECO are subject to Section 305 of the Federal Power Act that makes it unlawful for a public utility to make or pay a dividend from any funds "properly included in its capital account." Management believes that this Federal Power Act restriction, as applied to CL&P, PSNH and WMECO, would not be construed or applied by the FERC to prohibit the payment of dividends for lawful and legitimate business purposes from retained earnings. In addition, certain state statutes may impose additional limitations on such companies and on Yankee Gas. Such state law restrictions do not restrict payment of dividends from retained earnings or net income. CL&P, PSNH, WMECO and Yankee Gas also have a revolving credit agreement that imposes leverage restrictions including consolidated total debt to total capitalization ratio requirements. The Retained Earnings balances subject to these leverage restrictions are $1.652 billion for NU, $735.9 million for CL&P, $388.9 million for PSNH and $115.5 million for WMECO as of December 31, 2011. PSNH is further required to reserve an additional amount under its FERC hydroelectric license conditions. As of December 31, 2011, approximately $11.9 million of PSNH's Retained Earnings is subject to restriction under its FERC hydroelectric license conditions. . As of December 31, 2011, NU, CL&P, PSNH, WMECO and Yankee Gas were in compliance with all such provisions of its credit agreement that may restrict the payment of dividends