Medical Expenses Payable - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Insurance [Abstract]
Remaining claim amounts payment period	3 years
Claims reserve estimates, excluding provision	$ 5,951	$ 871

Claims reserve estimates, excluding provision from prior year claims and claims adjustment expense.

No definition available.

Name:	alhc_ClaimsReserveEstimatesExcludingProvisionFromPriorYearClaimsAndClaimsAdjustmentExpense
Namespace Prefix:	alhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration