Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash Flows From Operating Activities:
Net income	$ 253	$ 235
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	324	295
Amortization of nuclear fuel	22	0
Amortization of debt issuance costs and premium/discounts	4	5
Deferred income taxes and investment tax credits, net	31	26
Allowance for equity funds used during construction	(8)	(7)
Stock-based compensation costs	4	6
Other	11	8
Changes in assets and liabilities:
Receivables	(117)	(5)
Inventories	72	54
Accounts and wages payable	(235)	(252)
Taxes accrued	47	60
Regulatory assets and liabilities	75	(421)
Assets, other	(54)	(9)
Liabilities, other	(26)	(34)
Pension and other postretirement benefits	(15)	4
Net cash provided by (used in) operating activities	388	(35)
Cash Flows From Investing Activities:
Capital expenditures	(774)	(887)
Nuclear fuel expenditures	(16)	(1)
Purchases of securities – nuclear decommissioning trust fund	(97)	(152)
Sales and maturities of securities – nuclear decommissioning trust fund	92	150
Other	15	1
Net cash used in investing activities	(780)	(889)
Cash Flows From Financing Activities:
Dividends on common stock	(152)	(140)
Dividends paid to noncontrolling interest holders	(1)	(2)
Short-term debt, net	555	399
Issuances of long-term debt	0	450
Issuances of common stock	5	125
Redemptions of Ameren Illinois preferred stock	0	(13)
Employee payroll taxes related to stock-based compensation	(16)	(17)
Debt issuance costs	0	(3)
Other	0	(4)
Net cash provided by financing activities	391	795
Net change in cash, cash equivalents, and restricted cash	(1)	(129)
Cash, cash equivalents, and restricted cash at beginning of year	155	301
Cash, cash equivalents, and restricted cash at end of period	154	172
Union Electric Company
Cash Flows From Operating Activities:
Net income	51	48
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	189	171
Amortization of nuclear fuel	22	0
Amortization of debt issuance costs and premium/discounts	1	1
Deferred income taxes and investment tax credits, net	4	4
Allowance for equity funds used during construction	(4)	(4)
Other	0	3
Changes in assets and liabilities:
Receivables	7	20
Inventories	5	24
Accounts and wages payable	(201)	(201)
Taxes accrued	41	39
Regulatory assets and liabilities	(3)	(164)
Assets, other	(34)	13
Liabilities, other	(18)	(9)
Pension and other postretirement benefits	(4)	4
Net cash provided by (used in) operating activities	56	(51)
Cash Flows From Investing Activities:
Capital expenditures	(414)	(534)
Nuclear fuel expenditures	(16)	(1)
Purchases of securities – nuclear decommissioning trust fund	(97)	(152)
Sales and maturities of securities – nuclear decommissioning trust fund	92	150
Money pool advances, net	0	139
Other	18	0
Net cash used in investing activities	(417)	(398)
Cash Flows From Financing Activities:
Dividends on preferred stock	(1)	(1)
Short-term debt, net	363	204
Capital contributions from parent	0	113
Net cash provided by financing activities	362	316
Net change in cash, cash equivalents, and restricted cash	1	(133)
Cash, cash equivalents, and restricted cash at beginning of year	8	145
Cash, cash equivalents, and restricted cash at end of period	9	12
Ameren Illinois Company
Cash Flows From Operating Activities:
Net income	169	150
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	124	115
Amortization of debt issuance costs and premium/discounts	3	3
Deferred income taxes and investment tax credits, net	27	53
Allowance for equity funds used during construction	(4)	(3)
Other	2	6
Changes in assets and liabilities:
Receivables	(126)	(24)
Inventories	67	30
Accounts and wages payable	(18)	(40)
Taxes accrued	32	3
Regulatory assets and liabilities	79	(255)
Assets, other	(18)	(15)
Liabilities, other	13	(9)
Pension and other postretirement benefits	(8)	(1)
Net cash provided by (used in) operating activities	342	13
Cash Flows From Investing Activities:
Capital expenditures	(342)	(337)
Net cash used in investing activities	(342)	(337)
Cash Flows From Financing Activities:
Dividends on preferred stock	0	(1)
Short-term debt, net	4	323
Money pool borrowings, net	0	(19)
Capital contributions from parent	0	40
Redemption of preferred stock	0	(13)
Other	0	(4)
Net cash provided by financing activities	4	326
Net change in cash, cash equivalents, and restricted cash	4	2
Cash, cash equivalents, and restricted cash at beginning of year	133	147
Cash, cash equivalents, and restricted cash at end of period	$ 137	$ 149