Stock-Based Compensation - Stock Option Activity (Details) - 2014 Equity Incentive Plan, 2023 Equity Incentive Plan and Peak Bio 2022 Long Term Incentive Plan - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Options Outstanding at beginning of the period	3,963,964,688
Number of shares, Granted	10,452,672,000
Number of shares, Forfeited	(26,350,000)
Number of shares, Options Outstanding at end of the period	14,390,286,688		3,963,964,688
Number of shares, Exercisable options at end of the period	1,604,153,355
Weighted average exercise price, Outstanding at beginning of the period	$ 0.01
Weighted average exercise price, Forfeited	0.03
Weighted average exercise price, Outstanding at end of the period			$ 0.01
Options exercisable at end of the period, Weighted average exercise price	$ 0.01
Weighted average remaining contractual life, Options outstanding during the period (in years)	9 years 3 months 18 days		7 years 6 months
Weighted average remaining contractual term, Options exercisable at end of the period (in years)	4 years 3 months 18 days
Aggregate intrinsic value, Options outstanding at end of the period	$ 1
Aggregate intrinsic value, Options exercisable at end of the period	$ 1
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value per share of options granted	$ 0.01	$ 0.01