Notes Payable - Future Maturities of Principal Repayment of Convertible Notes (Details) $ in Thousands	Mar. 31, 2024 USD ($)
Notes Payable [Abstract]
2024 (remaining)	$ 357
2025	2,590
Total	$ 2,947

Future maturities of principal repayment of convertible notes remainder of fiscal year.

No definition available.

Name:	icu_FutureMaturitiesOfPrincipalRepaymentOfConvertibleNotesRemainderOfFiscalYear
Namespace Prefix:	icu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant