Retirement-Related Benefits - Nonpension Postretirement Contributions (Details) - U.S. Defined Benefit Non Pension Postretirement Plans - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Retirement-related benefits disclosures
Contributions by employer - Cash		$ 227
Contributions by employer - Noncash	$ 200

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No definition available.

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