Shareholders' Equity - Repurchases (Details) - 2016 Repurchase Program - USD ($)	Dec. 31, 2020	Nov. 02, 2016
Equity, Class of Treasury Stock [Line Items]
Authorized		$ 15,000,000,000.0
Remaining as of December 31, 2020	$ 13,900,000,000

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.

No definition available.

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