REGULATORY MATTERS (Summary of PPFAC Rates) (Detail) (Subsequent Event [Member], TUCSON ELECTRIC POWER COMPANY)	10 Months Ended	1 Months Ended
	Apr. 30, 2014	Apr. 30, 2014 May Through September [Member]	Apr. 30, 2014 October Through March [Member]
Schedule of Regulatory Matters Summary Of PPFAC Rates [Table] [Line Items]
PPFAC Rate	0.0014	0.0010	0.0050