Summary of significant accounting policies - Schedule of Error Corrections and Prior Period Adjustments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Income before income taxes	$ 314.4	$ 407.2	$ 77.4
Net income	230.9	305.1	54.5
Revision of Prior Period, Adjustment
Disaggregation of Revenue [Line Items]
Income before income taxes	7.1
Net income	5.3
Services
Disaggregation of Revenue [Line Items]
Services	334.9	166.7	80.0
Services | Revision of Prior Period, Adjustment
Disaggregation of Revenue [Line Items]
Services	28.8
Cost of CDMO	16.2
Leases
Disaggregation of Revenue [Line Items]
Leases	299.7	283.8	0.0
Leases | Revision of Prior Period, Adjustment
Disaggregation of Revenue [Line Items]
Leases	(5.5)
Total CDMO
Disaggregation of Revenue [Line Items]
Total CDMO	634.6	450.5	80.0
Cost of CDMO	375.5	$ 132.0	$ 61.2
Total CDMO | Revision of Prior Period, Adjustment
Disaggregation of Revenue [Line Items]
Total CDMO	$ 23.3