Stock-based Compensation, RSU Activity (Details) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) Director $ / shares shares
RSU Awards [Member]
Restricted Stock Units [Abstract]
Number of members of board of directors receiving grant of RSU award \| Director			2
Stock-based compensation \| $	$ 1.4	$ 3.9	$ 18.9
Number of Shares Underlying RSUs [Roll Forward]
Nonvested RSUs, beginning balance (in shares)	2,018,449	4,586,972	0
Granted (in shares)	786,938	66,666	4,861,315
Vested (in shares)	(1,685,101)	(798,575)	(274,343)
Forfeited (in shares)	(273,117)	(1,836,614)	0
Non-vested RSUs, ending balance (in shares)	847,169	2,018,449	4,586,972
Weighted Average Grant-Date Fair Value [Abstract]
Non-vested RSUs, beginning balance (in dollars per share) \| $ / shares	$ 8.41	$ 8	$ 0
Granted (in dollars per share) \| $ / shares	1.67	3	8.03
Vested (in dollars per share) \| $ / shares	8.55	8.24	8.53
Forfeited (in dollars per share) \| $ / shares	5.89	7.26	0
Non-vested RSUs, ending balance (in dollars per share) \| $ / shares	$ 2.68	$ 8.41	$ 8
RSU Awards [Member] \| Former Chief Executive Officer [Member]
Restricted Stock Units [Abstract]
Stock-based compensation \| $	$ (4.7)
Number of Shares Underlying RSUs [Roll Forward]
Forfeited (in shares)	(1,731,371)
RSU Awards Subject to Service and Performance Conditions [Member]
Restricted Stock Units [Abstract]
Stock-based compensation \| $			$ 18.6
RSU Awards Subject to Service and Performance Conditions [Member] \| Former Chief Executive Officer [Member]
Number of Shares Underlying RSUs [Roll Forward]
Granted (in shares)			1,703,460
RSU Awards Subject to Service and Performance Conditions [Member] \| General Counsel [Member]
Number of Shares Underlying RSUs [Roll Forward]
Granted (in shares)			170,346
RSU Awards Subject to Service and/or Performance Condition [Member] \| Interim Executive Chairman and Two Members of Board of Directors [Member]
Number of Shares Underlying RSUs [Roll Forward]
Granted (in shares)			1,800,000
RSU Awards Subject to Service, Market and Performance Conditions [Member] \| Former Chief Executive Officer [Member]
Number of Shares Underlying RSUs [Roll Forward]
Granted (in shares)			453,777

The number of members of the board of directors receiving an award of restricted stock units (RSU).

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Amount of noncash expense (credit) for award of restricted stock (reversal of expense) under share-based payment arrangement.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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