CONSOLIDATED STATEMENTS OF INCOME (LOSS) (Constellation Energy Group, Inc. and Subsidiaries) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Revenues
Nonregulated revenues	$ 10,773.0	$ 10,883.0	$ 12,024.3
Regulated electric revenues	2,320.7	2,752.1	2,820.7
Regulated gas revenues	664.5	704.9	753.8
Total revenues	13,758.2	14,340.0	15,598.8
Expenses
Fuel and purchased energy expenses	9,396.6	10,001.7	11,013.1
Fuel and purchased energy expenses from affiliate	888.4	900.8	122.5
Operating expenses	1,934.9	1,691.1	2,228.0
Merger costs	117.9		145.8
Impairment losses and other costs	891.0	2,476.8	124.7
Workforce reduction costs			12.6
Depreciation, depletion, accretion, and amortization	589.3	519.5	651.4
Taxes other than income taxes	308.0	263.9	290.4
Total expenses	14,126.1	15,853.8	14,588.5
Equity Investment Earnings (Losses)	19.8	25.0	(6.1)
Gain on U.S. Department of Energy Settlement	93.8
Gain on Sale of Interest in CENG			7,445.6
Net Gain (Loss) on Divestitures	57.3	245.8	(468.8)
(Loss) Income from Operations	(197.0)	(1,243.0)	7,981.0
Other Expenses	(75.3)	(76.7)	(140.7)
Fixed Charges
Interest expense	276.6	310.8	437.2
Interest capitalized and allowance for borrowed funds used during construction	(11.2)	(33.0)	(87.1)
Total fixed charges	265.4	277.8	350.1
(Loss) Income from Continuing Operations Before Income Taxes	(537.7)	(1,597.5)	7,490.2
Income Tax (Benefit) Expense	(230.9)	(665.7)	2,986.8
Net (Loss) Income	(306.8)	(931.8)	4,503.4
Net Income Attributable to Noncontrolling Interests and BGE Preference Stock Dividends	33.5	50.8	60.0
Net (Loss) Income Attributable to Common Stock	$ (340.3)	$ (982.6)	$ 4,443.4
Average Shares of Common Stock Outstanding-Basic (in shares)	200.1	200.5	199.3
Average Shares of Common Stock Outstanding-Diluted (in shares)	200.1	200.5	200.3
(Loss) Earnings Per Common Share-Basic (in dollars per share)	$ (1.70)	$ (4.90)	$ 22.29
(Loss) Earnings Per Common Share-Diluted (in dollars per share)	$ (1.70)	$ (4.90)	$ 22.19
Dividends Declared Per Common Share (in dollars per share)	$ 0.96	$ 0.96	$ 0.96