Share-Based Payments - Restricted Stock Units and Restricted Stock Awards Activities (Details) $ / shares in Units, shares in Thousands, $ in Millions	6 Months Ended
Jun. 30, 2021 USD ($) $ / shares shares
Restricted Stock Units (RSUs)
Restricted stock rights activity
Restricted stock rights at the beginning of the period (in shares) \| shares	7,102
Restricted stock rights, granted (in shares) \| shares	4,215
Restricted stock rights, vested (in shares) \| shares	(2,360)
Restricted stock rights, forfeited (in shares) \| shares	(632)
Restricted stock rights at the end of the period (in shares) \| shares	8,325
Restricted stock rights, weighted-average grant date fair value information
Restricted stock rights, weighted-average grant date fair value at the beginning of the period (in dollars per share) \| $ / shares	$ 82.50
Restricted stock rights, weighted-average grant date fair value, granted (in dollars per share) \| $ / shares	96.57
Restricted stock rights, weighted-average grant date fair value, vested (in dollars per share) \| $ / shares	104.79
Restricted stock rights, weighted-average grant date fair value, forfeited (in dollars per share) \| $ / shares	70.59
Restricted stock rights, weighted-average grant date fair value (in dollars per share) ending balance \| $ / shares	$ 84.96
Share-based compensation, unrecognized compensation \| $	$ 411
Share-based compensation, unrecognized compensation weighted-average period of recognition	1 year 7 months 17 days
Performance Based Restricted Stock Units
Restricted stock rights, weighted-average grant date fair value information
Share-based compensation, unrecognized compensation \| $	$ 140
Share-based compensation, unrecognized compensation weighted-average period of recognition	1 year 3 months

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

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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