Income Taxes - Indefinite Reinvestment of Foreign Earnings (Details) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Abstract]
Increase to shareholders' net income resulting from indefinite reinvestment of foreign earnings	$ 42,000,000	$ 37,000,000	$ 17,000,000
Accumulated permanently reinvested foreign earnings	1,100,000,000
Cumulative unrecognized deferred tax liabilities	$ 160,000,000

The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to permanently reinvested foreign earnings.

No definition available.

Name:	ci_IncomeTaxReconciliationPermanentlyReinvestedForeignEarnings
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration