CONDENSED CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
OPERATING REVENUES	$ 1,183,322	$ 1,166,922	$ 2,805,637	$ 2,759,483
OPERATING EXPENSES
Fuel and purchased power	310,469	336,120	777,475	832,253
Operations and maintenance	224,305	217,568	658,294	703,042
Depreciation and amortization	133,912	120,428	387,278	362,977
Taxes other than income taxes	45,169	41,284	133,294	125,902
Other expenses	3,385	264	5,479	2,141
Total	717,240	715,664	1,961,820	2,026,315
OPERATING INCOME	466,082	451,258	843,817	733,168
OTHER INCOME (DEDUCTIONS)
Allowance for equity funds used during construction	12,728	10,194	32,666	31,079
Other income (Note 8)	1,091	71	2,055	385
Other expense (Note 8)	(4,993)	(5,205)	(12,495)	(12,085)
Total	8,826	5,060	22,226	19,379
INTEREST EXPENSE
Interest charges	55,644	51,293	162,477	154,886
Allowance for borrowed funds used during construction	(6,000)	(4,321)	(15,378)	(14,849)
Total	49,644	46,972	147,099	140,037
INCOME BEFORE INCOME TAXES	425,264	409,346	718,944	612,510
INCOME TAXES	144,319	141,446	237,497	209,102
NET INCOME	280,945	267,900	481,447	403,408
Less: Net income attributable to noncontrolling interests (Note 5)	4,873	4,873	14,620	14,620
NET INCOME ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 276,072	$ 263,027	$ 466,827	$ 388,788
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING - BASIC (in shares)	111,835	111,416	111,787	111,363
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING - DILUTED (in shares)	112,401	112,100	112,314	111,987
EARNINGS PER WEIGHTED-AVERAGE COMMON SHARE OUTSTANDING
Net income attributable to common shareholders - basic (in dollars per share)	$ 2.47	$ 2.36	$ 4.18	$ 3.49
Net income attributable to common shareholders - diluted (in dollars per share)	2.46	2.35	4.16	3.47
DIVIDENDS DECLARED PER SHARE (in dollars per share)	$ 0	$ 0	$ 1.31	$ 1.25
APS
ELECTRIC OPERATING REVENUES	$ 1,178,106	$ 1,166,359	$ 2,797,590	$ 2,752,748
OPERATING EXPENSES
Fuel and purchased power	309,045	339,510	786,041	835,643
Operations and maintenance	215,264	209,366	635,769	681,789
Depreciation and amortization	133,486	120,013	386,010	362,492
Income taxes	153,425	148,945	257,182	225,239
Taxes other than income taxes	44,833	40,924	132,281	125,370
Total	856,053	858,758	2,197,283	2,230,533
OPERATING INCOME	322,053	307,601	600,307	522,215
OTHER INCOME (DEDUCTIONS)
Income taxes	6,892	5,753	13,474	9,289
Allowance for equity funds used during construction	12,728	10,194	32,666	31,079
Other income (Note 8)	1,478	567	3,682	6,924
Other expense (Note 8)	(6,262)	(3,776)	(16,290)	(12,956)
Total	14,836	12,738	33,532	34,336
INTEREST EXPENSE
Interest on long-term debt	50,429	46,970	147,909	142,692
Interest on short-term borrowings	2,140	2,401	6,599	6,408
Debt discount, premium and expense	1,191	1,196	3,566	3,529
Allowance for borrowed funds used during construction	(6,000)	(4,321)	(15,378)	(14,359)
Total	47,760	46,246	142,696	138,270
NET INCOME	289,129	274,093	491,143	418,281
Less: Net income attributable to noncontrolling interests (Note 5)	4,873	4,873	14,620	14,620
NET INCOME ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 284,256	$ 269,220	$ 476,523	$ 403,661