Schedule I - Condensed Financial Information, Intercompany Liabilities (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Cigna [Member]
Condensed Financial Statements, Captions [Line Items]
Intercompany liabilities	$ 4,965
Cigna [Member] \| Old Cigna [Member]
Condensed Financial Statements, Captions [Line Items]
Intercompany liabilities	$ 4,300
Average monthly interest rate on intercompany payables	2.33%
Old Cigna [Member]
Condensed Financial Statements, Captions [Line Items]
Intercompany liabilities		$ 2,980
Old Cigna [Member] \| Cigna Holdings Incorporated [Member]
Condensed Financial Statements, Captions [Line Items]
Intercompany liabilities		$ 2,800
Average monthly interest rate on intercompany payables		1.47%

Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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