Compensation Plans (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3,400	$ 2,900
Awards expected to be settled with stock	3,190	$ 2,769
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 27,900
Weighted average recognition period for unrecognized stock-based compensation expense	2 years 9 months 18 days

Share-based Payment Arrangement, Noncash Expense, Including Liabilities Settled

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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