CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Net Income	$ 5,157	$ 15,775	$ 74,898	$ 74,863
Other Comprehensive Income (Loss), net of deferred income taxes	250	350	456	551
Comprehensive Income	5,407	16,125	75,354	75,414
Less:
Preferred Stock Dividends of Subsidiary, Noncontrolling Interests	13	26	39	65
Comprehensive Income attributable to UIL Holdings	$ 5,394	$ 16,099	$ 75,315	$ 75,349

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of income (loss) attributable to redeemable noncontrolling preferred unit holders.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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