Repurchases of Common Stock - Schedule of Repurchases of Common Stock (Details) - USD ($) $ / shares in Units, $ in Millions	5 Months Ended	12 Months Ended
Apr. 29, 2018	Dec. 31, 2018	Dec. 31, 2017
Equity [Abstract]
Number of Shares Repurchased (in shares)	23,749,647	16,738,758	7,010,889
Average Price Paid Per Share (usd per share)	$ 63.07	$ 62.96	$ 63.34
Total Purchase Price	$ 1,498	$ 1,054	$ 444

Number of shares that have been repurchased and retired during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration