Stock Based Awards and Other Equity Instruments - Summary of Stock Option Activity (Details) - Employee Stock Option $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) $ / shares shares
Options Outstanding
Options Outstanding, Beginning balance | shares	5,462
Options Outstanding, Granted | shares	164
Options Outstanding, Cancelled or expired | shares	(1,699)	[1]
Options Outstanding, Ending balance | shares	3,927
Options Outstanding, Exercisable | shares	2,893
Options Outstanding, Vested and expected to vest | shares	3,781	[2]
Weighted Average Exercise Price per share
Options Outstanding, Weighted Average Exercise Price, Beginning Balance | $ / shares	$ 43.48
Options Granted, Weighted Average Exercise Price | $ / shares	20.15
Options Cancelled or expired, Weighted Average Exercise Price | $ / shares	59.54	[1]
Options Outstanding, Weighted Average Exercise Price, Ending balance | $ / shares	35.56
Options Exercisable, Weighted Average Exercise Price | $ / shares	39.3
Options Vested and expected to vest, Weighted Average Exercise Price | $ / shares	$ 35.88	[2]
Weighted Average Remaining Contractual Life and Aggregate Intrinsic Value
Options Outstanding, Weighted Average Remaining Contractual Life	5 years 2 months 12 days
Options Exercisable, Weighted Average Remaining Contractual Life	4 years 1 month 6 days
Options Vested and expected to vest, Weighted Average Remaining Contractual Life	5 years 1 month 6 days	[2]
Options Outstanding, Aggregate Intrinsic Value | $	$ 2
Options Exercisable, Aggregate Intrinsic Value | $	1
Options Vested and expected to vest, Aggregate Intrinsic Value | $	$ 2	[2]

[1] Inclusive of 1,100,000 stock options awarded in August 2013 to our former CEO, Stephen Kaufer, that expired during the third quarter of 2023. The expiration of these stock options had no impact to our stock-based compensation expense under GAAP during the third quarter of 2023.

[2] The Company accounts for forfeitures as they occur, rather than estimate expected forfeitures as allowed under GAAP and therefore do not include a forfeiture rate in our vested and expected to vest calculation unless necessary for a performance condition award.