Consolidated Statements of Cash Flows - NPC - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income attributable to parent	$ 5,790	$ 6,943	$ 2,950
Adjustments to reconcile net income to net cash flows from operating activities:
Allowance for equity funds	(126)	(165)	(173)
Changes in regulatory assets and liabilities	(668)	(415)	153
Deferred income taxes and investment tax credits, net	646	1,880	290
Other, net	(169)	(77)	23
Changes in other operating assets and liabilities, net of effects from acquisitions:
Trade receivables and other assets	553	(1,318)	(372)
Accrued property, income and other taxes, net	(489)	(134)	(16)
Accounts payable and other liabilities	163	501	(26)
Net cash flows from operating activities	8,692	6,224	6,206
Cash flows from investing activities:
Capital expenditures	(6,611)	(6,765)	(7,364)
Other, net	(74)	76	51
Net cash flows from investing activities	(5,763)	(13,165)	(8,963)
Cash flows from financing activities:
Net (repayments of) proceeds from short-term debt	(276)	(939)	684
Other, net	(79)	(134)	(37)
Net cash flows from financing activities	(3,131)	7,103	3,124
Net change in cash and cash equivalents and restricted cash and cash equivalents	(201)	177	385
Cash and cash equivalents and restricted cash and cash equivalents at beginning of period	1,445	1,268	883
Cash and cash equivalents and restricted cash and cash equivalents at end of period	1,244	1,445	1,268
NPC
Cash flows from operating activities:
Net income attributable to parent	303	295	264
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	406	361	357
Allowance for equity funds	(7)	(7)	(5)
Changes in regulatory assets and liabilities	(19)	(42)	27
Deferred income taxes and investment tax credits, net	0	(10)	(32)
Deferred energy	(245)	(44)	51
Amortization of deferred energy	11	(41)	43
Other, net	0	2	(5)
Changes in other operating assets and liabilities, net of effects from acquisitions:
Trade receivables and other assets	6	45	19
Inventories	5	(7)	1
Accrued property, income and other taxes, net	(18)	5	(13)
Accounts payable and other liabilities	63	(90)	(6)
Net cash flows from operating activities	505	467	701
Cash flows from investing activities:
Capital expenditures	(449)	(455)	(409)
Proceeds from sale of assets	0	26	2
Other, net	2	0	0
Net cash flows from investing activities	(447)	(429)	(407)
Cash flows from financing activities:
Proceeds from long-term debt	0	718	495
Repayments of long-term debt	0	(575)	(500)
Net (repayments of) proceeds from short-term debt	180	0	0
Dividends paid	(213)	(155)	(371)
Other, net	(16)	(15)	(14)
Net cash flows from financing activities	(49)	(27)	(390)
Net change in cash and cash equivalents and restricted cash and cash equivalents	9	11	(96)
Cash and cash equivalents and restricted cash and cash equivalents at beginning of period	36	25	121
Cash and cash equivalents and restricted cash and cash equivalents at end of period	$ 45	$ 36	$ 25