Shareholders' Equity and Redeemable Non-controlling Interests, Shareholders' Equity, Share repurchase authorization (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
	Sep. 30, 2019	Mar. 31, 2020	Mar. 31, 2019
Share repurchase authorization [Line Items]
Cash paid for shares repurchased		$ 4	$ 512
Sept 2019 Share Repurchase Authorization [Member]
Share repurchase authorization [Line Items]
Stock repurchase authorization shares authorized to be repurchased	33,300,000
Stock repurchase authorization expiration date	Mar. 12, 2021
Shares repurchased (in shares)		50,685
Average purchase price (in dollars per share)		$ 78.93
Total purchase price, including commissions and fees		$ 4
June 2018 Share Repurchase Authorization [Member]
Share repurchase authorization [Line Items]
Shares repurchased (in shares)			5,648,900
Average purchase price (in dollars per share)			$ 86.38
Total purchase price, including commissions and fees			$ 488