Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Related Party Transaction [Line Items]
Print procurement services	$ 0.5	$ 0.4	$ 1.3	$ 1.3
Insurance and risk management services	0.1	$ 0.0	0.1	$ 0.2
Arthur J.Gallagher Co [Member]
Related Party Transaction [Line Items]
Net amount receivable from related parties	$ 0.3		$ 0.3		$ 0.4