Other Financial Information - Schedule of Other Accrued Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Employee-related Liabilities, Current	$ 555		$ 455
Accrued Liabilities and Other Liabilities	365
Other Accrued Liabilities, Current	2,029		2,202
Accrued Income Taxes, Current	190		713
Accrued Liabilities, Current	$ 3,139	$ 3,255	3,370
Japan Tobacco
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Accrued Liabilities and Other Liabilities			$ 0

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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