Consolidated Statements of Income (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Operating revenues (includes revenue taxes of $86 for 2012, $9 for 2011 and $0 for 2010)	$ 3,922		$ 2,338		$ 2,373
Operating expenses
Cost of goods sold	1,791		1,097		1,164
Operation and maintenance	921		501		497
Depreciation and amortization	415		186		160
Nicor merger expenses	20		57		6
Taxes other than income taxes	165		57		46
Total operating expenses	3,312		1,898		1,873
Operating income	610		440		500
Other income (expenses), net	24		7		(1)
Interest expenses, net	(184)		(136)		(109)
Total other expense	(160)		(129)		(110)
Earnings before income taxes	450		311		390
Income tax expenses	164		125		140
Net income	286		186		250
Less net income attributable to the noncontrolling interest	15		14		16
Net income attributable to AGL Resources Inc.	$ 271		$ 172		$ 234
Per common share data
Basic earnings per common share attributable to AGL Resources Inc. common shareholders (in Dollars per share)	$ 2.32		$ 2.14		$ 3.02
Diluted earnings per common share attributable to AGL Resources Inc. common shareholders (in Dollars per share)	$ 2.31		$ 2.12		$ 3.00
Cash dividends declared per common share (in Dollars per share)	$ 1.74		$ 1.90		$ 1.76
Weighted average number of common shares outstanding
Basic (in Shares)	117.0	[1]	80.4	[1]	77.4	[1]
Diluted (in Shares)	117.5		80.9		77.8

[1] Daily weighted average shares outstanding.