Revenue from contracts with customers Remaining performance obligations (Details 3) $ in Millions	Dec. 31, 2020 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 2,100.0
Remaining performance obligation, expected timing of satisfaction, start date: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 1,600.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Remaining performance obligation, expected timing of satisfaction, start date: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 298.8
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	13 months
Remaining performance obligation, expected timing of satisfaction, start date: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 234.3
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	25 months