CHANGES IN ACCUMULATED OTHER COMPREHENSIVE INCOME BY COMPONENT (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Gains and Losses on Cash Flow Hedges
Tax Benefit	$ 1,801
Realized Losses on Cash Flow Hedges, Net of Taxes	(2,752)
Amortization of SERP and Defined Benefit Plans
Prior Service Costs	(1,488)
Tax (Expense) Benefit	572	(608)	804
Amortization, Net of Taxes	(916)	840	(1,158)
Total Reclassification from Other Comprehensive Income for the Period	(3,668)
TUCSON ELECTRIC POWER COMPANY
Gains and Losses on Cash Flow Hedges
Tax Benefit	1,718
Realized Losses on Cash Flow Hedges, Net of Taxes	(2,624)
Amortization of SERP and Defined Benefit Plans
Prior Service Costs	(1,488)
Tax (Expense) Benefit	572	(608)	804
Amortization, Net of Taxes	(916)	840	(1,158)
Total Reclassification from Other Comprehensive Income for the Period	(3,540)
Interest Rate Contract Long Term Debt [Member]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(1,377)
Interest Rate Contract Long Term Debt [Member] | TUCSON ELECTRIC POWER COMPANY
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(1,166)
Interest Rate contract Capital Leases [Member]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(2,429)
Interest Rate contract Capital Leases [Member] | TUCSON ELECTRIC POWER COMPANY
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(2,429)
Commodity Contract [Member]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(747)
Commodity Contract [Member] | TUCSON ELECTRIC POWER COMPANY
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	$ (747)