Acquisitions and Dispositions - Total Purchase Price Paid (Details) - First Data - USD ($) $ / shares in Units, shares in Millions, $ in Millions	Jul. 29, 2019	Jul. 26, 2019
Business Acquisition [Line Items]
Repayment of First Data debt	$ 16,414
Total purchase price	46,475
Share price of shares issued for acquisition (in dollars per share)		$ 102.30
Common Shares
Business Acquisition [Line Items]
Fair value of exchanges	$ 29,293
Number of shares issued for acquisition (in shares)	286
Equity Awards
Business Acquisition [Line Items]
Fair value of exchanges	$ 768
Number of shares issued for acquisition (in shares)	15

Number of shares of equity interests issued or issuable to acquire entity.

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