Share-based Compensation - Stock Option 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
Options, Weighted Average Exercise Price
Share-based compensation expense	$ 1.7	$ 1.6
ABP Sub Inc. 2019 Incentive Award Plan
Options, Number of Shares
Outstanding, beginning of period	47,955
Outstanding, end of period	47,955		47,955
Exercisable, end of period	43,819
Options, Weighted Average Exercise Price
Outstanding, beginning of period	$ 720
Outstanding, end of period	720		$ 720
Exercisable, end of period	$ 720
Weighted average remaining contractual life of options outstanding	5 years 9 months 18 days		6 years
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
ABP Sub Inc. 2019 Incentive Award Plan \| Stock options
Options, Weighted Average Exercise Price
Share-based compensation expense	$ 0.6	$ 0.8

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

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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