Share-based Compensation - Restricted Stock Units Activity Under 2019 Incentive Award Plan (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Other than options, Weighted Average Exercise Price
Share-based compensation expense	$ 1.7	$ 1.6
ABP Sub Inc. 2019 Incentive Award Plan
Other than options, Weighted Average Exercise Price
Unrecognized compensation expense related to non-vested stock options	$ 1.3		$ 1.8
Weighted-average remaining requisite service period for which unrecognized compensation expense	3 months		4 months
RSU \| ABP Sub Inc. 2019 Incentive Award Plan
Other than options, Number of Shares
Outstanding, beginning of period	11,398
Outstanding, ending of period	11,398		11,398
Other than options, Weighted Average Exercise Price
Outstanding, beginning of period	$ 780.48
Outstanding, ending of period	$ 780.48		$ 780.48
Share-based compensation expense	$ 0.3	$ 0.4
Unrecognized compensation expense related to non-vested stock options	$ 2.6		$ 3.0
Weighted-average remaining requisite service period for which unrecognized compensation expense	19 months		21 months
RSU \| ABP Sub Inc. 2019 Incentive Award Plan \| Earnout Vesting
Other than options, Weighted Average Exercise Price
Unrecognized compensation expense related to other than options	$ 4.2		$ 4.3

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

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