CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
PROPERTY, PLANT AND EQUIPMENT (Notes 1, 6 and 9)
Accumulated depreciation of Palo Verde sale leaseback	$ 241,405	$ 237,535
Accumulated amortization on intangible assets	582,272	603,637
Accumulated amortization on nuclear fuel	$ 144,070	$ 147,202
EQUITY
Common stock, par value	$ 0	$ 0
Common stock, authorized shares	150,000,000	150,000,000
Common stock, issued shares	111,816,170	111,392,053
Treasury stock at cost, shares	64,463	55,317
ARIZONA PUBLIC SERVICE COMPANY
PROPERTY, PLANT AND EQUIPMENT (Notes 1, 6 and 9)
Accumulated depreciation of Palo Verde sale leaseback	$ 241,405	$ 237,535
Accumulated amortization on intangible assets	581,135	603,637
Accumulated amortization on nuclear fuel	$ 144,070	$ 147,202