Consolidated Statement of Income (Loss) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Operating Revenues:
Electric	$ 1,106		$ 1,088
Gas	488		387
Total operating revenues	1,594		1,475
Operating Expenses:
Fuel	204		213
Purchased power	112		151
Gas purchased for resale	304		230
Other operations and maintenance	420		399
Depreciation and amortization	181		175
Taxes other than income taxes	127		122
Total operating expenses	1,348		1,290
Operating Income	246		185
Other Income and Expenses:
Miscellaneous income	18	[1]	15	[1]
Miscellaneous expense	9	[1]	8	[1]
Total other income (expense)	9		7
Interest Charges	92		101
Income Before Income Taxes	163		91
Income Taxes	64		35
Income from Continuing Operations	99		56
Loss from Discontinued Operations, Net of Taxes (Note 12)	(1)		(199)
Net Income (Loss)	98		(143)
Comprehensive Income (Loss)	96		(152)
Less: Net Income (Loss) Attributable to Noncontrolling Interests:
Net Income from Continuing Operations Attributable to Noncontrolling Interests	2		2
Net Income (Loss):
Continuing Operations	97		54
Discontinued Operations	(1)		(199)
Net Income (Loss)	96		(145)
Income (Loss) from Continuing Operations, Per Basic Share	$ 0.40		$ 0.22
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share	$ 0.00		$ (0.82)
Earnings Per Share, Basic	$ 0.40		$ (0.60)
Dividends per Common Share	$ 0.40		$ 0.40
Average Common Shares Outstanding - Basic	242.6		242.6
Union Electric Company
Operating Revenues:
Electric	749		732
Gas	68		64
Total operating revenues	817		796
Operating Expenses:
Fuel	204		213
Purchased power	33		26
Gas purchased for resale	40		37
Other operations and maintenance	227		221
Depreciation and amortization	116		111
Taxes other than income taxes	78		77
Total operating expenses	698		685
Operating Income	119		111
Other Income and Expenses:
Miscellaneous income	14		14
Miscellaneous expense	4		5
Total other income (expense)	10		9
Interest Charges	52		60
Income Before Income Taxes	77		60
Income Taxes	29		19
Net Income (Loss)	48		41
Other Comprehensive Income	0		0
Comprehensive Income (Loss)	48		41
Net Income (Loss):
Net Income (Loss)	48		41
Preferred Stock Dividends	1		1
Net Income Available to Common Stockholder	47		40
Ameren Illinois Company
Operating Revenues:
Electric	353		360
Gas	421		324
Total operating revenues	774		684
Operating Expenses:
Purchased power	81		127
Gas purchased for resale	264		193
Other operations and maintenance	200		176
Depreciation and amortization	63		61
Taxes other than income taxes	46		42
Total operating expenses	654		599
Operating Income	120		85
Other Income and Expenses:
Miscellaneous income	3		1
Miscellaneous expense	4		3
Total other income (expense)	(1)		(2)
Interest Charges	30		31
Income Before Income Taxes	89		52
Income Taxes	35		20
Net Income (Loss)	54		32
Pension and other postretirement benefit plan activity, net of income taxes (benefit)	(1)		(1)
Comprehensive Income (Loss)	53		31
Net Income (Loss):
Net Income (Loss)	54		32
Preferred Stock Dividends	1		1
Net Income Available to Common Stockholder	$ 53		$ 31

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