Consolidated Statement Of Cash Flows - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash Flows From Operating Activities:
Net income (loss)		$ 636	$ 592	$ 295
(Income) Loss from discontinued operations, net of tax		(51)	1	223
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for Callaway construction and operating license		69		0
Depreciation and amortization		777	710	666
Amortization of nuclear fuel		97	81	71
Amortization of debt issuance costs and premium/discounts		22	22	24
Deferred income taxes and investment tax credits, net		369	451	410
Allowance for equity funds used during construction	[1]	(30)	(34)	(37)
Share-based Compensation		24	25	27
Other		(10)	(24)	23
Changes in assets and liabilities:
Receivables		83	31	(60)
Materials and supplies		(14)	3	60
Accounts and wages payable		(2)	10	81
Taxes accrued		(24)	(44)	(195)
Regulatory assets and liabilities		94	(281)	29
Assets, other		53	30	20
Liabilities, other		(56)	(28)	(14)
Pension and other postretirement benefits		(9)	(10)	(28)
Counterparty collateral, net		(7)	22	41
Net cash provided by operating activities - continuing operations		2,021	1,557	1,636
Net cash provided by operating activities - discontinued operations		(4)	(6)	57
Net cash provided by operating activities		2,017	1,551	1,693
Cash Flows From Investing Activities:
Capital expenditures		(1,917)	(1,785)	(1,379)
Nuclear fuel expenditures		(52)	(74)	(45)
Purchases of securities - nuclear decommissioning trust fund		(363)	(405)	(214)
Sales and maturities of securities - nuclear decommissioning trust fund		349	391	196
Proceeds from Collection of Notes Receivable		20	95	6
Contributions to Note Receivable		(8)	(89)	(5)
Other		20	11	1
Net cash used in investing activities - continuing operations		(1,951)	(1,856)	(1,440)
Net cash used in investing activities - discontinued operations		(25)	139	(283)
Net cash used in investing activities		(1,976)	(1,717)	(1,723)
Cash Flows From Financing Activities:
Dividends on common stock		(402)	(390)	(388)
Dividends paid to noncontrolling interest holders		(6)	(6)	(6)
Short-term debt, net		(413)	346	368
Maturities, redemptions, and repurchases of long-term debt		(120)	(697)	(399)
Issuances of Long-term debt		1,197	898	278
Capital issuance costs		(12)	(11)	(2)
Other		2	1	0
Net cash provided by (used in) financing activities		246	141	(149)
Net change in cash and cash equivalents		287	(25)	(179)
Cash and cash equivalents at beginning of year		5	30	209
Cash and cash equivalents at end of year		292	5	30
Cash Paid (Refunded) During the Year:
Interest net of capitalized		335	333	393
Income taxes, net		(15)	(27)	8
Union Electric Company
Cash Flows From Operating Activities:
Net income (loss)		355	393	398
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for Callaway construction and operating license		69	0	0
Depreciation and amortization		476	442	419
Amortization of nuclear fuel		97	81	71
FAC prudence review charge				26
Amortization of debt issuance costs and premium/discounts		6	7	7
Deferred income taxes and investment tax credits, net		82	245	65
Allowance for equity funds used during construction		(22)	(32)	(31)
Other		2	3	1
Changes in assets and liabilities:
Receivables		72	(10)	(59)
Materials and supplies		(39)	8	45
Accounts and wages payable		3	25	42
Taxes accrued		1	(197)	100
Regulatory assets and liabilities		117	(68)	68
Assets, other		26	52	18
Liabilities, other		4	0	(29)
Pension and other postretirement benefits		(2)	1	2
Net cash provided by operating activities		1,247	950	1,143
Cash Flows From Investing Activities:
Capital expenditures		(622)	(747)	(648)
Nuclear fuel expenditures		(52)	(74)	(45)
Purchases of securities - nuclear decommissioning trust fund		(363)	(405)	(214)
Sales and maturities of securities - nuclear decommissioning trust fund		349	391	196
Money pool advances, net		36		(24)
Other			(2)	0
Net cash used in investing activities		(724)	(837)	(687)
Cash Flows From Financing Activities:
Dividends on common stock		(575)	(340)	(460)
Return of capital to parent		0	(215)
Dividends on preferred stock		(3)	(3)	(3)
Money pool borrowings, net		0	(105)	105
Short-term debt, net		(97)	97
Maturities, redemptions, and repurchases of long-term debt		(120)	(109)	(249)
Issuances of Long-term debt		249	350
Capital issuance costs		(3)	(3)
Capital contribution from parent		224	215	4
Net cash provided by (used in) financing activities		(325)	(113)	(603)
Net change in cash and cash equivalents		198	0	(147)
Cash and cash equivalents at beginning of year		1	1	148
Cash and cash equivalents at end of year		199	1	1
Noncash Or Part Noncash Capital Contribution From Parent		38	9	0
Cash Paid (Refunded) During the Year:
Interest net of capitalized		212	203	212
Income taxes, net		72	215	86
Ameren Illinois Company
Cash Flows From Operating Activities:
Net income (loss)		217	204	163
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization		292	259	238
Amortization of debt issuance costs and premium/discounts		14	13	15
Deferred income taxes and investment tax credits, net		221	196	104
Allowance for equity funds used during construction		(8)	(2)	(6)
Other		(14)	(19)	4
Changes in assets and liabilities:
Receivables		16	(13)	50
Materials and supplies		25	(4)	15
Accounts and wages payable		37	7	19
Taxes accrued		(2)	(7)	28
Regulatory assets and liabilities		(26)	(215)	(35)
Assets, other		17	15	5
Liabilities, other		(27)	1	10
Pension and other postretirement benefits		(4)	(6)	(8)
Counterparty collateral, net		(3)	14	43
Net cash provided by operating activities		763	445	651
Cash Flows From Investing Activities:
Capital expenditures		(918)	(835)	(701)
Other		5	7	6
Net cash used in investing activities		(913)	(828)	(695)
Cash Flows From Financing Activities:
Dividends on common stock			0	(110)
Dividends on preferred stock		(3)	(3)	(3)
Money pool borrowings, net		(15)	(41)	32
Short-term debt, net		(32)	32
Maturities, redemptions, and repurchases of long-term debt		0	(163)	(150)
Issuances of Long-term debt		248	548	278
Capital issuance costs		(3)	(6)	(2)
Capital contribution from parent		25	15
Other			1	0
Net cash provided by (used in) financing activities		220	383	45
Net change in cash and cash equivalents		70	0	1
Cash and cash equivalents at beginning of year		1	1	0
Cash and cash equivalents at end of year		71	1	1
Cash Paid (Refunded) During the Year:
Interest net of capitalized		120	110	112
Income taxes, net		$ (113)	$ (44)	$ (23)

[1] Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations.