Other Financial Information - Other Accrued Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Other Financial Information [Abstract]
Output tax payable	$ 599	$ 376
Branded prescription drug fee	405	649
Income taxes payable	390	65
Other accrued expenses	2,084	2,082
Total other accrued liabilities	$ 3,478	$ 3,172