CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income	$ 259,950	$ 233,325
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization including nuclear fuel	350,536	343,173
Deferred fuel and purchased power	(135,905)	(26,473)
Deferred fuel and purchased power amortization	10,828	(4,815)
Allowance for equity funds used during construction	(19,197)	(16,508)
Deferred income taxes	30,231	22,229
Deferred investment tax credit	(3,651)	(3,386)
Stock compensation	13,484	9,130
Changes in current assets and liabilities:
Customer and other receivables	(41,138)	7,767
Accrued unbilled revenues	(91,721)	(63,413)
Materials, supplies and fossil fuel	(31,449)	10,295
Income tax receivable	6,792	4,605
Other current assets	(14,021)	(24,896)
Accounts payable	66,558	17,772
Accrued taxes	23,486	6,588
Other current liabilities	(39,638)	(45,334)
Change in other long-term assets	(118,036)	(4,885)
Change in other long-term liabilities	45,241	(96,142)
Net cash flow provided by operating activities	312,350	369,032
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(681,148)	(676,973)
Contributions in aid of construction	32,104	31,295
Allowance for borrowed funds used during construction	(10,193)	(8,825)
Proceeds from nuclear decommissioning trusts sales and other special use funds	587,842	391,859
Investment in nuclear decommissioning trusts and other special use funds	(588,982)	(393,000)
Other	10,809	3,123
Net cash flow used for investing activities	(649,568)	(652,521)
CASH FLOWS FROM FINANCING ACTIVITIES
Issuance of long-term debt	150,000	1,088,886
Short-term borrowing and (repayments) — net	354,700	184,225
Short-term debt borrowings under revolving credit facility	0	751,690
Short-term debt repayments under revolving credit facility	(19,000)	(758,690)
Dividends paid on common stock	(183,500)	(172,566)
Repayment of long-term debt	0	(800,000)
Common stock equity issuance — net of purchases	(176)	(2,204)
Distributions to noncontrolling interests	(10,628)	(11,372)
Net cash flow provided by financing activities	291,396	279,969
NET DECREASE IN CASH AND CASH EQUIVALENTS	(45,822)	(3,520)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	59,968	10,283
CASH AND CASH EQUIVALENTS AT END OF PERIOD	14,146	6,763
APS
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income	263,647	242,210
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization including nuclear fuel	350,494	343,130
Deferred fuel and purchased power	(135,905)	(26,473)
Deferred fuel and purchased power amortization	10,828	(4,815)
Allowance for equity funds used during construction	(19,197)	(16,508)
Deferred income taxes	23,161	15,233
Deferred investment tax credit	(3,651)	(3,386)
Changes in current assets and liabilities:
Customer and other receivables	(41,963)	824
Accrued unbilled revenues	(91,721)	(63,413)
Materials, supplies and fossil fuel	(31,449)	10,295
Income tax receivable	0	7,313
Other current assets	(12,636)	(19,752)
Accounts payable	66,192	17,915
Accrued taxes	44,439	14,551
Other current liabilities	(39,749)	(40,381)
Change in other long-term assets	(114,154)	(7,356)
Change in other long-term liabilities	46,327	(91,983)
Net cash flow provided by operating activities	314,663	377,404
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(681,148)	(676,973)
Contributions in aid of construction	32,104	31,295
Allowance for borrowed funds used during construction	(10,193)	(8,825)
Proceeds from nuclear decommissioning trusts sales and other special use funds	587,842	391,859
Investment in nuclear decommissioning trusts and other special use funds	(588,982)	(393,000)
Other	2,986	(169)
Net cash flow used for investing activities	(657,391)	(655,813)
CASH FLOWS FROM FINANCING ACTIVITIES
Issuance of long-term debt	0	591,936
Short-term borrowing and (repayments) — net	495,000	219,900
Short-term debt borrowings under revolving credit facility	0	540,000
Short-term debt repayments under revolving credit facility	0	(540,000)
Dividends paid on common stock	(187,000)	(176,000)
Repayment of long-term debt	0	(350,000)
Distributions to noncontrolling interests	(10,628)	(11,372)
Net cash flow provided by financing activities	297,372	274,464
NET DECREASE IN CASH AND CASH EQUIVALENTS	(45,356)	(3,945)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	57,310	10,169
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 11,954	$ 6,224