Pension Plan (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Components of net periodic benefit:
Interest cost	$ 0.7	$ 0.7	$ 1.4	$ 1.5
Expected return on plan assets	$ (0.9)	$ (0.9)	(1.8)	(1.9)
Net periodic benefit			$ (0.4)	$ (0.4)