Derivative Instruments - Impact on Statements of Income, Fair Value Hedges (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Gains/(losses) recorded in income
Derivatives	$ 736	$ (5,265)	$ 1,417
Hedged items	412	6,214	(337)
Income statement impact	1,148	949	1,080
Income statement impact of excluded components
Amortization approach	(566)
Changes in fair value	1,125
Income statement impact due to:
Hedge ineffectiveness		11	(3)
Excluded components		938	1,083
OCI impact
Derivatives - Gains/(losses) recorded in OCI	(140)
Interest rate
Gains/(losses) recorded in income
Derivatives	(1,145)	(481)	(482)
Hedged items	1,782	1,359	1,338
Income statement impact	637	878	856
Income statement impact of excluded components
Amortization approach	0
Changes in fair value	623
Income statement impact due to:
Hedge ineffectiveness		(18)	6
Excluded components		896	850
OCI impact
Derivatives - Gains/(losses) recorded in OCI	0
Foreign exchange
Gains/(losses) recorded in income
Derivatives	1,092	(3,509)	2,435
Hedged items	(616)	3,507	(2,261)
Income statement impact	476	(2)	174
Income statement impact of excluded components
Amortization approach	(566)
Changes in fair value	476
Income statement impact due to:
Hedge ineffectiveness		0	0
Excluded components		(2)	174
OCI impact
Derivatives - Gains/(losses) recorded in OCI	(140)
Commodity
Gains/(losses) recorded in income
Derivatives	789	(1,275)	(536)
Hedged items	(754)	1,348	586
Income statement impact	35	73	50
Income statement impact of excluded components
Amortization approach	0
Changes in fair value	26
Income statement impact due to:
Hedge ineffectiveness		29	(9)
Excluded components		$ 44	$ 59
OCI impact
Derivatives - Gains/(losses) recorded in OCI	$ 0

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Net gain (loss) relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

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