Income Taxes, Valuation allowance and tax carryforwards (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income taxes
Valuation allowance, related to the foreign net operating loss carryforwards and U.S. state tax credits	$ 44.9	$ 40.1
Change in the valuation allowance, related to foreign net operating loss and foreign and U.S. state credit carryforwards	4.8	$ 4.9
Foreign
Income taxes
Loss carryforwards	156.7
Operating loss carryforwards to expire or be refunded	114.3
Tax credit carryforwards	0.6
Tax credit carryforwards to expire or be refunded	0.4
U.S. Federal
Income taxes
Loss carryforwards	13.8
Operating loss carryforwards to expire or be refunded	13.8
Tax credit carryforwards	0.9
Tax credit carryforwards to expire or be refunded	0.9
U.S. State
Income taxes
Loss carryforwards	84.1
Operating loss carryforwards to expire or be refunded	84.1
Tax credit carryforwards	17.0
Tax credit carryforwards to expire or be refunded	$ 11.0