Fair value measurement - BMS warrants - Narrative (Details) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2020 USD ($) item $ / shares	Dec. 31, 2019 USD ($)	Apr. 06, 2015 $ / shares
Collaboration arrangements
Number of warrant types	2
Fair value of derivative financial instruments | $	$ 0.8	$ 3.1
BMS Warrants
Collaboration arrangements
Exercise price in respect of each warrant | $ / shares	$ 55.07		$ 33.84
Number of trading days used to calculate Volume Weighted Average Price ("VWAP")	20 days
Number of days prior to purchase or exercise used to calculate Volume Weighted Average Price ("VWAP")	5 days
Compounded annual growth rate used to determine fair value of exercise price	10.00%
BMS Warrants | Minimum
Collaboration arrangements
Period in which the exercise of warrants is expected to occur after balance sheet date (in years)	4 years
BMS Warrants | Maximum
Collaboration arrangements
Period in which the exercise of warrants is expected to occur after balance sheet date (in years)	5 years
BMS First Warrant | Minimum
Collaboration arrangements
Probability of the occurrence of events allowing warrant exercises	0.00%
BMS First Warrant | Maximum
Collaboration arrangements
Probability of the occurrence of events allowing warrant exercises	44.00%
BMS First Warrant | Weighted average input
Collaboration arrangements
Probability of the occurrence of events allowing warrant exercises	24.00%
BMS Second Warrant | Minimum
Collaboration arrangements
Probability of the occurrence of events allowing warrant exercises	0.00%
BMS Second Warrant | Maximum
Collaboration arrangements
Probability of the occurrence of events allowing warrant exercises	11.00%
BMS Second Warrant | Weighted average input
Collaboration arrangements
Probability of the occurrence of events allowing warrant exercises	5.00%
uniQure N.V. | Bristol Myers Squibb | First Six New Targets Or Designation Of Sixth Target
Collaboration arrangements
Ownership percentage required per agreement	14.90%
uniQure N.V. | Bristol Myers Squibb | First Nine New Targets Or Designation Of Ninth Target
Collaboration arrangements
Ownership percentage required per agreement	19.90%
BMS arrangement | BMS Warrants
Collaboration arrangements
Additional change in fair value of derivatives | $	$ (0.7)
BMS arrangement | Bristol Myers Squibb
Collaboration arrangements
Number of potential targets included in collaborative agreement	10
Number of Collaboration Targets	4
Number of Collaboration Targets actually are designated	4
BMS arrangement | Bristol Myers Squibb | First Six New Targets Or Designation Of Sixth Target
Collaboration arrangements
Number of potential targets included in collaborative agreement	7
Number of Collaboration Targets	6
BMS arrangement | Bristol Myers Squibb | First Nine New Targets Or Designation Of Ninth Target
Collaboration arrangements
Number of potential targets included in collaborative agreement	10
Number of Collaboration Targets	9