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Equity - Narrative (Details) - USD ($) $ in Billions	7 Months Ended	12 Months Ended
	Apr. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
Equity [Abstract]
Common stock, shares authorized		6,500,000,000		6,500,000,000
Preferred stock, shares authorized				20,000,000
Accelerated Share Repurchase Agreement, October 29, 2018
Accelerated Share Repurchases [Line Items]
Purchases of treasury stock (in shares)			56,700,000
Accelerated Share Repurchase Agreement
Accelerated Share Repurchases [Line Items]
Purchases of treasury stock (in shares)	64,400,000	7,700,000
Payment under ASR agreement			$ 5

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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.

+ References

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Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 25
-Paragraph 5
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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Number of shares that have been repurchased during the period and are being held in treasury.

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