Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act of 2017.

No definition available.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Accounting and Disclosure Changes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2018	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash receipts from operating cash flows		$ 2,765	$ 2,354
Cash receipts from investing cash flows		$ (2,286)	(1,211)
Accounting Standards Update 2018-2
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of tax effects from accumulated other comprehensive income to retained earnings	$ 58
Accounting Standards Update 2016-15
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash receipts from operating cash flows			(151)
Cash receipts from investing cash flows			$ 151