Summary of significant accounting policies - Restricted cash (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Summary of significant accounting policies
Separate cash balance to collateralize corporate credit cards with a bank	$ 40	$ 20
Separate cash balance for the landlord	$ 20	$ 5

Amount of cash restricted as to the benefit of the landlord in connection with the Company’s office space lease in California (the “Lease”), classified as noncurrent.

No definition available.

Name:	akro_RestrictedCashNoncurrentLease
Namespace Prefix:	akro_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant