Note 1 - Organization and Significant Accounting Policies - Calculation of Diluted Shares (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Net loss attributable to BioLife Solutions											$ (1,657)	$ (25,005)
Less: Preferred stock dividends and accumulated deficit impact of preferred stock redemption												(339)
Net income (loss) attributable to common stockholders	$ 8,380	$ 3,425	$ (19,161)	$ (24,545)	$ (26,439)	$ 4,767	$ (14,909)	$ (21,672)	$ (4,640)	$ (46,217)	$ (1,657)	$ (25,344)
Basic and diluted weighted average shares outstanding (in shares)	19,735,364	18,819,459	18,648,397	17,273,412	15,180,169	14,098,610	18,734,401	14,642,378	19,071,722	15,529,026	19,460,299	16,256,465
Basic and Diluted (in dollars per share)											$ (0.09)	$ (1.56)