Employee Benefit Plans - Narratives (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure
Accrued pension liability	$ 8.6	$ 9.4
Estimated net periodic pension expense to be amortized over the next fiscal year	0.9
Projected benefit obligation	62.5	58.5	$ 53.6
Fair value of plan assets	53.9	49.1	42.8
Multiemployer plan, contributions by employer	0.5	0.5	0.4
Defined contribution expense	4.9	8.7	8.2
Compensation expense	0.3	0.3	$ 0.4
Hudson
Defined Benefit Plan Disclosure
Accrued pension liability	1.0	0.8
Projected benefit obligation	2.9	2.9
Fair value of plan assets	$ 2.0	$ 2.0