Condensed Consolidated Statements of Changes in Equity (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Additional Paid-in Capital, value of stock	$ 31,950	$ 32,184	$ 31,950	$ 32,184	$ 31,362	$ 32,433	$ 32,022	$ 31,848
Common Stock [Member]
Additional Paid-in Capital, value of stock	$ 2	$ 2	$ 2	$ 2	$ 2	$ 2	$ 2	$ 2
Dividends declared, amount per share	$ 3.30	$ 2.88	$ 6.60	$ 5.76

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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