Accounting Policies and Supplemental Disclosures - Video and Music Content (Details) - USD ($) $ in Billions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Accounting Policies [Abstract]
Digital video and music content, capitalized costs	$ 8.6		$ 8.6		$ 6.8
Digital video and music content, expense	$ 3.1	$ 2.8	$ 6.2	$ 5.2