CONSOLIDATED STATEMENTS OF INCOME (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
OPERATING REVENUES
Electric Utility operating revenues	$ 2,211.5	$ 2,109.9	$ 1,751.2
Natural Gas Midstream Operations operating revenues	1,704.4	1,607.0	1,118.5
Total operating revenues	3,915.9	3,716.9	2,869.7
COST OF GOODS SOLD (exclusive of depreciation and amortization shown below)
Electric Utility cost of goods sold	966.0	952.6	748.7
Natural Gas Midstream Operations cost of goods sold	1,311.9	1,234.8	809.0
Total cost of goods sold	2,277.9	2,187.4	1,557.7
Gross margin on revenues	1,638.0	1,529.5	1,312.0
OPERATING EXPENSES
Other operation and maintenance	581.2	549.8	466.8
Depreciation and amortization	307.1	291.3	262.6
Impairment of assets	6.3	1.1	3.1
Gain on insurance proceeds	(3.0)	0	0
Taxes other than income	99.7	93.4	87.6
Total operating expenses	991.3	935.6	820.1
OPERATING INCOME	646.7	593.9	491.9
OTHER INCOME (EXPENSE)
Interest income	0.5	0	1.4
Allowance for equity funds used during construction	20.4	11.4	15.1
Other income	19.3	13.7	27.5
Other expense	(21.7)	(17.9)	(16.3)
Net other income	18.5	7.2	27.7
INTEREST EXPENSE
Interest on long-term debt	146.1	139.3	137.3
Allowance for borrowed funds used during construction	(10.4)	(5.5)	(8.3)
Interest on short-term debt and other interest charges	5.2	5.9	8.4
Interest expense	140.9	139.7	137.4
INCOME BEFORE TAXES	524.3	461.4	382.2
INCOME TAX EXPENSE	160.7	161.0	121.1
NET INCOME	363.6	300.4	261.1
Less: Net income attributable to noncontrolling interests	20.7	5.1	2.8
NET INCOME ATTRIBUTABLE TO OGE ENERGY	$ 342.9	$ 295.3	$ 258.3
BASIC AVERAGE COMMON SHARES OUTSTANDING (in shares)	97.9	97.3	96.2
DILUTED AVERAGE COMMON SHARES OUTSTANDING (in shares)	99.2	98.9	97.2
BASIC EARNINGS PER AVERAGE COMMON SHARE ATTRIBUTABLE TO OGE ENERGY COMMON SHAREHOLDERS (in dollars per share)	$ 3.50	$ 3.03	$ 2.68
DILUTED EARNINGS PER AVERAGE COMMON SHARE ATTRIBUTABLE TO OGE ENERGY COMMON SHAREHOLDERS (in dollars per share)	$ 3.45	$ 2.99	$ 2.66
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 1.5175	$ 1.4625	$ 1.4275