Warrants - Schedule of Weighted-Average Strike Price and Time to Maturity for Each Warrant Tranche (Details) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Class of Warrant or Right [Line Items]
Weighted-Average Strike Price	$ 0.9132
Liability Classified Warrants [Member] \| Investor D Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant Share Equivalents	3,158,086	6,368,289
Weighted-Average Strike Price	$ 0.5	$ 0.5
Weighted-Average Time to Maturity	4 years 4 months 24 days	4 years 7 months 24 days
Liability Classified Warrants [Member] \| Private Placement Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant Share Equivalents	5,738,000	5,738,000
Weighted-Average Strike Price	$ 11.5	$ 11.5
Weighted-Average Time to Maturity	3 years 6 months 25 days	3 years 9 months 25 days
Liability Classified Warrants [Member] \| PIPE Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant Share Equivalents	500,000	500,000
Weighted-Average Strike Price	$ 11.5	$ 11.5
Weighted-Average Time to Maturity	3 years 6 months 25 days	3 years 9 months 25 days
Equity Classified Warrants [Member] \| Investor E Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant Share Equivalents	16,261,142
Weighted-Average Strike Price	$ 0.83
Weighted-Average Time to Maturity	4 years 5 months 12 days
Equity Classified Warrants [Member] \| Placement Agent warrants [Member]
Class of Warrant or Right [Line Items]
Warrant Share Equivalents	542,038
Weighted-Average Strike Price	$ 0.91
Weighted-Average Time to Maturity	5 years 3 months
Equity Classified Warrants [Member] \| Public Stockholders Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant Share Equivalents	10,550,000	10,550,000
Weighted-Average Strike Price	$ 11.5	$ 11.5
Weighted-Average Time to Maturity	3 years 6 months 25 days	3 years 9 months 25 days
Equity Classified Warrants [Member] \| Legacy SeaStar Inc. Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant Share Equivalents	48,914	48,914
Weighted-Average Strike Price	$ 10	$ 10
Weighted-Average Time to Maturity	2 years 1 month 17 days	2 years 4 months 17 days

Exercise price per share or per unit of warrants or rights outstanding.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-3

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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Number of warrants or rights outstanding.

+ References

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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