Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended				3 Months Ended
	Mar. 31, 2011	Mar. 31, 2010	Jun. 30, 2010	Jun. 30, 2011 TEP [Member]	Jun. 30, 2011 Unisource Energy Electric [Member]	Mar. 31, 2010 National Energy Corporation [Member]	Mar. 31, 2011 Unisource Energy and TEP [Member]
Income Taxes (Textuals) [Abstract]
Capital loss from sale of subsidiary		$ 12,000,000
Deferred tax asset		5,000,000
Deferred tax assets related to the investment in Nations Energy Corporation, net of valuation allowance		2,000,000				3,000,000
Valuation allowance for deferred tax asset on Capital loss			3,000,000
Deferred tax assets expected to realized due to the 5-year capital loss carryforward limitation			2,000,000
Corporate income tax rate	6.968%
Corporate Income tax rate reduction in every year	0.50%
Corporate ultimate Income tax rate	4.90%
Reduction in net deferred tax liabilities due to reduction in tax rate							13,000,000
Unrecognized tax benefits decreases resulting from change in accounting method				$ 10,000,000	$ 13,000,000