Assets held for rent - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Assets held for rent, depreciation expense	$ 0.5	$ 0.6	$ 0.9	$ 1.2

The amount of depreciation expenses recognized for assets held for rent.

No definition available.

Name:	blfs_AssetsHeldForRentDepreciation
Namespace Prefix:	blfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration