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Impact of COVID-19 - COVID-19 Relief Funding (Details) - USD ($)			5 Months Ended		6 Months Ended		8 Months Ended	9 Months Ended		12 Months Ended
	Feb. 02, 2022	Sep. 28, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 29, 2021	Jan. 15, 2021	Apr. 30, 2020
Unusual Risk or Uncertainty [Line Items]
Long-term debt, gross							$ 423,000,000	$ 423,000,000	$ 357,000,000	$ 423,000,000	$ 423,000,000	$ 357,000,000
Principal repayments on debt											97,000,000	126,000,000	$ 139,000,000
Interest paid											$ 9,000,000	7,000,000	10,000,000
Warrants outstanding, term							5 years	5 years		5 years	5 years					5 years
Mark to market adjustment on warrant											$ 22,000,000	9,000,000	$ 0
Employee retention credit											17,000,000	16,000,000
The Coronavirus Aid, Relief, and Economic Security Act | PSP1 Promissory Note
Unusual Risk or Uncertainty [Line Items]
Funding received				$ 211,000,000
Proceeds from Payroll Support Program grant						$ 178,000,000			178,000,000
Deferred financing costs									1,000,000
The Coronavirus Aid, Relief, and Economic Security Act | Consolidated Appropriations Act of 2021 - PSP 2
Unusual Risk or Uncertainty [Line Items]
Funding received										$ 161,000,000
Proceeds from Payroll Support Program grant											143,000,000
The American Rescue Plan Act | American Rescue Plan Act - PSP 3
Unusual Risk or Uncertainty [Line Items]
Funding received			$ 150,000,000
Proceeds from Payroll Support Program grant					$ 135,000,000		$ 135,000,000
PSP Promissory Note Warrants | PSP1 Promissory Note
Unusual Risk or Uncertainty [Line Items]
Warrants to acquire common stock (in shares)																522,576
Exercise price of warrants (in dollars per share)																$ 6.36
PSP2 Promissory Note Warrants | Consolidated Appropriations Act of 2021 - PSP 2
Unusual Risk or Uncertainty [Line Items]
Warrants to acquire common stock (in shares)															157,313
Exercise price of warrants (in dollars per share)															$ 11.65
PSP3 Promissory Note Warrants | American Rescue Plan Act - PSP 3
Unusual Risk or Uncertainty [Line Items]
Warrants to acquire common stock (in shares)														79,961
Exercise price of warrants (in dollars per share)														$ 18.85
CARES Act Credit Agreement, Warrants
Unusual Risk or Uncertainty [Line Items]
Warrants to acquire common stock (in shares)		2,358,090
Exercise price of warrants (in dollars per share)		$ 6.36
Warrants outstanding, term		5 years
Unsecured Debt | PSP1 Promissory Note
Unusual Risk or Uncertainty [Line Items]
Unsecured low interest loan amount						$ 33,000,000
Term of grant						10 years
Unsecured Debt | Consolidated Appropriations Act of 2021 - PSP 2
Unusual Risk or Uncertainty [Line Items]
Unsecured low interest loan amount											$ 18,000,000
Term of grant											10 years
Unsecured Debt | PSP3 Promissory Note
Unusual Risk or Uncertainty [Line Items]
Unsecured low interest loan amount								$ 15,000,000
Term of grant											10 years
Line of Credit | CARES Credit Agreement
Unusual Risk or Uncertainty [Line Items]
Term of grant		5 years
Term loan amount		$ 574,000,000
Long-term debt, gross							150,000,000	150,000,000	150,000,000	150,000,000	$ 150,000,000	150,000,000
Line of Credit | CARES Credit Agreement | Subsequent Event
Unusual Risk or Uncertainty [Line Items]
Principal repayments on debt	$ 150,000,000
Interest paid	$ 1,000,000
Secured Debt | CARES Credit Agreement
Unusual Risk or Uncertainty [Line Items]
Long-term debt, gross							$ 150,000,000	$ 150,000,000	$ 150,000,000	$ 150,000,000	$ 150,000,000	$ 150,000,000

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