Commitments and Contingencies (Details 3) (USD $) In Millions, unless otherwise specified	0 Months Ended	9 Months Ended
	May 23, 2013 Four Corners New Mexico Tax Matter	Sep. 30, 2013 Four Corners ARIZONA PUBLIC SERVICE COMPANY	Sep. 30, 2013 Four Corners ARIZONA PUBLIC SERVICE COMPANY New Mexico Tax Matter	Sep. 30, 2013 Navajo Plant ARIZONA PUBLIC SERVICE COMPANY	Sep. 30, 2013 Cholla ARIZONA PUBLIC SERVICE COMPANY	Sep. 30, 2013 Cholla Units 1-3 ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters
Expected environmental cost		$ 300		$ 200	$ 200	$ 120
Coal severance surtax, penalty, and interest	30
Share of the assessment			$ 12