CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
PROPERTY, PLANT AND EQUIPMENT
Accumulated depreciation of Palo Verde sale leaseback	$ 256,884	$ 253,014
Accumulated amortization on intangible assets	737,694	698,500
Accumulated amortization on nuclear fuel	$ 133,122	$ 137,207
EQUITY
Common stock, authorized shares (in shares)	150,000,000	150,000,000
Common stock, issued shares (in shares)	113,014,528	112,760,051
Treasury stock at cost, shares (in shares)	87,608	72,006
Arizona Public Service Company
PROPERTY, PLANT AND EQUIPMENT
Accumulated depreciation of Palo Verde sale leaseback	$ 256,884	$ 253,014
Accumulated amortization on intangible assets	736,560	697,366
Accumulated amortization on nuclear fuel	$ 133,122	$ 137,207