Consolidated Statement of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Consolidated Statement of Comprehensive Income
Net actuarial gains (losses) and prior service cost and credits and amortization of net actuarial losses and prior service cost and credits, taxes	$ (238)	$ 47	$ (61)
Unrealized gains (losses) on marketable equity securities, taxes			(76)
Net (losses) gains on derivative instruments designated as cash flow hedges, taxes	$ (17)	$ 50	$ (43)

Amount, after reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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