Income Taxes - NOL, foreign earnings (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Income Tax [Line Items]
Uncertain tax benefit recorded	$ 2.4
Uncertain tax benefit recorded, increase from prior years	1.5
Uncertain tax benefit recorded, increase from deferred tax asset	0.4
Uncertain tax benefit recorded, increase from current year	0.5
Internal Revenue Service (IRS)
Income Tax [Line Items]
Net operating loss carryforward	54.5
Net operating loss carryforward, subject to expiration	6.1
Canada Revenue Agency
Income Tax [Line Items]
Net operating loss carryforward	42.3
Mexican Tax Authority
Income Tax [Line Items]
Net operating loss carryforward	$ 9.3
Carryforward period	10 years