Condensed Consolidated Statements of Income (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Operating revenues (includes revenue taxes of $68 for the three months in 2014 and $50 for the three months in 2013)	$ 2,462	[1]	$ 1,612	[1]
Operating expenses
Cost of goods sold	1,400	[1]	920	[1]
Operation and maintenance	289	[1]	231	[1]
Depreciation and amortization	93	[1]	102	[1]
Taxes other than income taxes	88	[1]	69	[1]
Total operating expenses	1,870	[1]	1,322	[1]
Operating income	592	[1]	290	[1]
Other income	3	[1]	5	[1]
Interest expense, net	(46)		(45)
Income before income taxes	549		250
Income tax expense	203		91
Income from continuing operations	346		159
(Loss) income from discontinued operations	(50)	[2],[3]	1	[2],[3]
Net income	296		160
Less net income attributable to the noncontrolling interest	12		10
Net income attributable to AGL Resources Inc.	$ 284	[2]	$ 150	[2]
Basic earnings (loss) per common share
Continuing operations (in Dollars per share)	$ 2.82	[2],[4]	$ 1.27	[2],[4]
Discontinued operations (in Dollars per share)	$ (0.43)	[2],[4]	$ 0.01	[2],[4]
Basic earnings per common share attributable to AGL Resources Inc. common shareholders (in Dollars per share)	$ 2.39	[2]	$ 1.28	[2]
Diluted earnings (loss) per common share
Continuing operations (in Dollars per share)	$ 2.81	[2],[4]	$ 1.26	[2],[4]
Discontinued operations (in Dollars per share)	$ (0.43)	[2],[4]	$ 0.01	[2],[4]
Diluted earnings per common share attributable to AGL Resources Inc. common shareholders (in Dollars per share)	$ 2.38	[2]	$ 1.27	[2]
Cash dividends declared per common share (in Dollars per share)	$ 0.49		$ 0.47
Weighted average number of common shares outstanding
Basic (in Shares)	118.5	[2],[5]	117.4	[2],[5]
Diluted (in Shares)	118.9	[2]	117.7	[2]

[1] Amounts revised to include prior period adjustments. See Note 13 for additional information.

[2] Amounts revised and or include prior period adjustments. See Note 13 for additional information.

[3] For additional information on our discontinued operations, see Note 12.

[4] Excludes net income attributable to the noncontrolling interest.

[5] Daily weighted average shares outstanding.