CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Constellation Energy Group, Inc. and Subsidiaries) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Net Income (Loss)	$ 97.9	$ (1,375.0)	$ 285.4	$ (1,099.9)
Hedging instruments:
Reclassification of net loss on hedging instruments from OCI to net income, net of taxes	10.1	135.4	97.7	423.3
Net unrealized loss on hedging instruments, net of taxes	(68.8)	(149.0)	(110.8)	(311.0)
Available-for-sale securities:
Reclassification of net gain on sales of securities from OCI to net income, net of taxes				(0.1)
Net unrealized gain on securities, net of taxes	4.1	0.2	4.2	0.4
Defined benefit obligations:
Amortization of net actuarial loss, prior service cost, and transition obligation included in net periodic benefit cost, net of taxes	8.6	5.6	24.3	16.4
Net unrealized (loss) gain on foreign currency, net of taxes	(5.2)	0.7	(3.4)	(8.3)
Other comprehensive (loss) gain - equity investment in CENG, net of taxes	(26.5)	22.3	(12.3)	10.1
Other comprehensive (loss) gain - other equity method investees, net of taxes	(7.3)	0.2	(7.3)	(0.3)
Comprehensive income (loss)	12.9	(1,359.6)	277.8	(969.4)
Less: Comprehensive income attributable to noncontrolling interests, net of taxes	24.2	31.5	42.1	42.5
Comprehensive (Loss) Income Attributable to Common Stock	$ (11.3)	$ (1,391.1)	$ 235.7	$ (1,011.9)