Discontinued Operations - Schedule of Discontinued Operations Reflected in Consolidated Condensed Statements of Income (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014
Expenses:
Loss from discontinued operations	$ (206)
HighMount [Member]
Revenues:
Other revenue, primarily operating	55
Total	55
Expenses:
Impairment of natural gas and oil properties	29
Operating	55
Interest	2
Total	86
Income (loss) before income tax	(31)
Income tax (expense) benefit	11
Loss from discontinued operations	(20)
CAC [Member]
Revenues:
Net investment income	41
Investment gains	1
Total	42
Expenses:
Insurance claims and policyholders' benefits	31
Other operating expenses	1
Total	32
Income (loss) before income tax	10
Income tax (expense) benefit	(3)
Results of discontinued operations, net of income tax	7
Loss on sale, net of tax benefit	(214)
Amounts attributable to noncontrolling interests	21
Loss from discontinued operations	$ (186)