Equity Activity - AOCI Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss) (net of tax)
Balance at the Beginning of the Period			$ 14,424	$ 12,014
Other comprehensive income/(loss)	$ 440	$ (724)	1,442	(280)
Balance at the End of the Period	17,159	13,450	17,159	13,450
Accumulated Other Comprehensive Income/(Loss)
Accumulated Other Comprehensive Income (Loss) (net of tax)
Balance at the Beginning of the Period			(29,607)	(27,875)
Other comprehensive income before reclassifications			117	(1,319)
Amount reclassified from accumulated other comprehensive income			1,326	1,039
Other comprehensive income/(loss)	440	(724)	1,442	(280)
Balance at the End of the Period	(28,164)	(28,155)	(28,164)	(28,155)
Net Unrealized Gains/(Losses) on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) (net of tax)
Balance at the Beginning of the Period			100	392
Other comprehensive income before reclassifications	21	27	(139)	301
Amount reclassified from accumulated other comprehensive income			12	(544)
Other comprehensive income/(loss)	29	(149)	(127)	(243)
Balance at the End of the Period	(28)	148	(28)	148
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) (net of tax)
Balance at the Beginning of the Period			(3,463)	(1,742)
Other comprehensive income before reclassifications			303	(1,593)
Amount reclassified from accumulated other comprehensive income			0	0
Other comprehensive income/(loss)	(49)	(1,043)	303	(1,593)
Balance at the End of the Period	(3,161)	(3,335)	(3,161)	(3,335)
Net Change Retirement-Related Benefit Plans
Accumulated Other Comprehensive Income (Loss) (net of tax)
Balance at the Beginning of the Period			(26,248)	(26,509)
Other comprehensive income before reclassifications			(25)	25
Amount reclassified from accumulated other comprehensive income			1,292	1,583
Other comprehensive income/(loss)	461	531	1,267	1,608
Balance at the End of the Period	(24,981)	(24,901)	(24,981)	(24,901)
Net Unrealized Gains/(Losses) on Available-For-Sale Securities
Accumulated Other Comprehensive Income (Loss) (net of tax)
Balance at the Beginning of the Period			5	(15)
Other comprehensive income before reclassifications	(1)	(63)	(22)	(52)
Amount reclassified from accumulated other comprehensive income			22	0
Other comprehensive income/(loss)	(1)	(62)	0	(52)
Balance at the End of the Period	$ 4	$ (67)	$ 4	$ (67)