Equity - Restricted stock units (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Other disclosures
Share-based payments subject to redemption	$ 37	$ 31	$ 36	$ 28	$ 21	$ 30
RSU
Share-based compensation
Vesting period	3 years
Restricted stock unit activity
Non-vested at the beginning of the period (in shares)	486
Granted (in shares)	203
Vested (in shares)	(126)
Cancelled (in shares)	(34)
Non-vested at the end of the period (in shares)	529
Weighted-average fair value per share
Non-vested at the beginning of the period (in dollars per share)	$ 88.34
Granted (in dollars per share)	88.86
Vested (in dollars per share)	91.28
Cancelled (in dollars per share)	86.85
Non-vested at the end of the period (in dollars per share)	$ 87.94
Other disclosures
Unrecognized compensation cost	$ 26
Weighted-average period for amortization of unrecognized compensation cost	2 years