CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Unaudited) - USD ($) $ in Thousands		Total	Common Stock	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests	Arizona Public Service Company	Arizona Public Service Company Common Stock	Arizona Public Service Company Additional Paid-In Capital	Arizona Public Service Company Retained Earnings	Arizona Public Service Company Accumulated Other Comprehensive Income (Loss)	Arizona Public Service Company Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2015			111,095,402	115,030					71,264,947
Balance at beginning of period at Dec. 31, 2015		$ 4,719,457	$ 2,541,668	$ (5,806)	$ 2,092,803	$ (44,748)	$ 135,540	$ 4,814,794	$ 178,162	$ 2,379,696	$ 2,148,493	$ (27,097)	$ 135,540
Increase (Decrease) in Shareholders' Equity
Net income		135,508			125,761		9,747	144,188			134,441		9,747
Other comprehensive income		1,029				1,029		1,169				1,169
Dividends on common stock		(138,947)			(138,947)			(139,000)			(139,000)
Issuance of common stock (in shares)			80,098
Issuance of common stock		7,830	$ 7,830
Purchase of treasury stock (in shares)	[1]			(71,962)
Purchase of treasury stock	[1]	(4,880)		$ (4,880)
Reissuance of treasury stock for stock-based compensation and other (in shares)				185,092
Reissuance of treasury stock for stock-based compensation and other		10,558		$ 10,556	2		0
Capital activities by noncontrolling interests		(11,372)					(11,372)	(11,372)					(11,372)
Ending balance (in shares) at Jun. 30, 2016			111,175,500	1,900					71,264,947
Balance at end of period at Jun. 30, 2016		4,719,183	$ 2,549,498	$ (130)	2,079,619	(43,719)	133,915	4,809,779	$ 178,162	2,379,696	2,143,934	(25,928)	133,915
Increase (Decrease) in Shareholders' Equity
Net income		126,182						132,062
Other comprehensive income		51						110
Ending balance (in shares) at Jun. 30, 2016			111,175,500	1,900					71,264,947
Balance at end of period at Jun. 30, 2016		$ 4,719,183	$ 2,549,498	$ (130)	2,079,619	(43,719)	133,915	4,809,779	$ 178,162	2,379,696	2,143,934	(25,928)	133,915
Beginning balance (in shares) at Dec. 31, 2016		111,392,053	111,392,053	55,317					71,264,947
Balance at beginning of period at Dec. 31, 2016		$ 4,935,912	$ 2,596,030	$ (4,133)	2,255,547	(43,822)	132,290	5,037,970	$ 178,162	2,421,696	2,331,245	(25,423)	132,290
Increase (Decrease) in Shareholders' Equity
Net income		200,502			190,755		9,747	202,017			192,270		9,747
Other comprehensive income		196				196		311				311
Dividends on common stock		(146,204)			(146,204)			(146,200)			(146,200)
Issuance of common stock (in shares)			250,627
Issuance of common stock		8,452	$ 8,452
Purchase of treasury stock (in shares)	[1]			(156,172)
Purchase of treasury stock	[1]	(12,430)		$ (12,430)
Reissuance of treasury stock for stock-based compensation and other (in shares)				192,191
Reissuance of treasury stock for stock-based compensation and other		15,021		$ 15,010	11		0
Capital activities by noncontrolling interests		$ (11,372)					(11,372)	(11,372)					(11,372)
Ending balance (in shares) at Jun. 30, 2017		111,642,680	111,642,680	19,298					71,264,947.000
Balance at end of period at Jun. 30, 2017		$ 4,990,077	$ 2,604,482	$ (1,553)	2,300,109	(43,626)	130,665	5,082,726	$ 178,162	2,421,696	2,377,315	(25,112)	130,665
Increase (Decrease) in Shareholders' Equity
Net income		172,317						173,982
Other comprehensive income		$ (763)						(737)
Ending balance (in shares) at Jun. 30, 2017		111,642,680	111,642,680	19,298					71,264,947.000
Balance at end of period at Jun. 30, 2017		$ 4,990,077	$ 2,604,482	$ (1,553)	$ 2,300,109	$ (43,626)	$ 130,665	$ 5,082,726	$ 178,162	$ 2,421,696	$ 2,377,315	$ (25,112)	$ 130,665

[1] Primarily represents shares of common stock withheld from certain stock awards for tax purposes.