Restructuring (Details) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($) segment	Dec. 31, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
Number of operating segments | segment	2
Severance costs		$ 3.3
Restructuring reserve	$ 2.8	2.8
Accounts Payable and Accrued Liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	2.2	2.2
Other Noncurrent Liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	$ 0.6	$ 0.6