Segment Information (Assets by Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Net pension income	$ (6.0)	$ (12.4)	$ (9.6)
Assets	2,417.1	2,469.1	2,452.4
United States Print and Related Services
Segment Reporting Information [Line Items]
Assets	2,038.7	2,057.8	2,060.9
International
Segment Reporting Information [Line Items]
Assets	302.5	341.5	329.5
Operating Segments
Segment Reporting Information [Line Items]
Assets	2,341.2	2,399.3	2,390.4
Corporate
Segment Reporting Information [Line Items]
Assets	$ 75.9	$ 69.8	$ 62.0