Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Net income	$ 60		$ 44		$ 356		$ 204
Retirement benefit plans
Reclassification of actuarial losses to net benefit cost (net of income tax of $2 and $3 for the three and six months ended June 30, 2014, and $3 and $5 for the three and six months ended June 30, 2013)	4		4		5		8
Reclassification of prior service credits to net benefit cost (net of income tax of $(1) for the six months ended June 30, 2013)	(1)				(1)		(1)
Retirement benefit plans	3	[1]	4	[1]	4	[1]	7	[1]
Cash flow hedges, net of tax
Net derivative instrument (losses) gains arising during the period (net of income tax of $1 for the three months ended June 30, 2013)			(1)		4		1
Reclassification of realized derivative instrument (gains) losses to net income (net of income tax of $(1) for the three and six months ended June 30, 2014 and $1 for the six months ended June 30, 2013)	(1)	[1]	(1)	[1]	(5)	[1]	1	[1]
Cash flow hedges, net	(1)	[1]	(2)	[1]	(1)	[1]	2	[1]
Other comprehensive income, net of tax	2	[1]	2	[1]	3	[1]	9	[1]
Comprehensive income	62		46		359		213
Less comprehensive income attributable to noncontrolling interest	2		1		14		11
Comprehensive income from continuing operations attributable to AGL Resources Inc.	$ 60		$ 45		$ 345		$ 202

[1] All amounts are net of income taxes. Amounts in parentheses indicate debits to accumulated other comprehensive loss.