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, 2014			110,649,762	78,400					71,264,947
Balance at end of period at Dec. 31, 2014		$ 4,519,102	$ 2,512,970	$ (3,401)	$ 1,926,065	$ (68,141)	$ 151,609	$ 4,629,852	$ 178,162	$ 2,379,696	$ 1,968,718	$ (48,333)	$ 151,609
Increase (Decrease) in Shareholders' Equity
Net income		20,727			16,122		4,605	24,473			19,868		4,605
Other comprehensive income		1,759				1,759		1,857				1,857
Other								1			1
Issuance of common stock (in shares)			159,730
Issuance of common stock		10,277	$ 10,277
Purchase of treasury stock (in shares)	[1]			(93,280)
Purchase of treasury stock	[1]	(6,095)		$ (6,095)
Reissuance of treasury stock for stock-based compensation and other (in shares)				109,896
Reissuance of treasury stock for stock-based compensation and other		7,237		$ 7,230	7
Ending balance (in shares) at Mar. 31, 2015			110,809,492	61,784					71,264,947
Balance at beginning of period at Mar. 31, 2015		$ 4,553,007	$ 2,523,247	$ (2,266)	1,942,194	(66,382)	156,214	4,656,183	$ 178,162	2,379,696	1,988,587	(46,476)	156,214
Beginning balance (in shares) at Dec. 31, 2015		111,095,402	111,095,402	115,030					71,264,947
Balance at end 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		9,326			4,453		4,873	12,126			7,253		4,873
Other comprehensive income		978				978		1,059				1,059
Other								1			0		1
Issuance of common stock (in shares)			52,122
Issuance of common stock		5,397	$ 5,397
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)				179,056
Reissuance of treasury stock for stock-based compensation and other		$ 10,135		$ 10,144	(10)		1
Ending balance (in shares) at Mar. 31, 2016		111,147,524	111,147,524	7,936					71,264,947
Balance at beginning of period at Mar. 31, 2016		$ 4,740,413	$ 2,547,065	$ (542)	$ 2,097,246	$ (43,770)	$ 140,414	$ 4,827,980	$ 178,162	$ 2,379,696	$ 2,155,746	$ (26,038)	$ 140,414

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