Segment Information - Long-Lived Assets, by Country (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 1,381	$ 1,564
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	518	666
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 863	$ 898