Pensions and Other Postretirement Benefits - Multi-employer Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Company contributions	$ 0.2	$ 0.5	$ 0.5
Central States Southeast and Southwest Areas Pension Fund
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension Protection Act Zone Status	Red	Red
Company contributions	$ 0.1	$ 0.1	0.1
PIUMPF
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension Protection Act Zone Status	Red	Red
Company contributions	$ 0.0	$ 0.1	0.1
Graphic Communications Conference of International Brotherhood of Teamster Pension Fund
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension Protection Act Zone Status	Red	Red
Company contributions	$ 0.1	$ 0.3	$ 0.3