Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Name:	us-gaap_ConvertibleNotesPayable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Related Party Transactions (Predecessor) - A1 Convertible Notes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2024	Dec. 31, 2022
Related Party Transactions
Estimated fair value of convertible notes	$ 0.0	$ 5.1
Alphaeon 1 LLC (A1) \| A1 Purchase Agreement \| 2021 A1 Convertible Notes
Related Party Transactions
Income (expense) related to change in fair value	0.5
Principal amount outstanding			$ 10.0
Estimated fair value of convertible notes			8.7
Alphaeon 1 LLC (A1) \| A1 Purchase Agreement \| 2022 A1 Convertible Notes
Related Party Transactions
Income (expense) related to change in fair value	0.7
Principal amount outstanding			14.5
Estimated fair value of convertible notes			$ 12.2
Alphaeon 1 LLC (A1) \| A1 Purchase Agreement \| 2023 A1 Convertible Notes
Related Party Transactions
Income (expense) related to change in fair value	$ 1.9