Recent Accounting Pronouncements (Impact of Adoption of ASU 2016-02) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Assets:
Property, plant and equipment, net	$ 259.4	$ 262.8	$ 263.7
Right of use asset, leases	95.8	90.9	0.0
Liabilities and stockholders' equity:
Current portion of long-term debt	31.6	39.4	39.5
Lease liabilities	20.6	24.1	0.0
Long-term debt, net	882.5	842.9	843.0
Long-term lease liabilities	84.6	76.6	11.0
Accumulated deficit	(611.3)	(656.3)	$ (656.8)
Accounting Standards Update 2016-02
Assets:
Property, plant and equipment, net		(0.9)
Right of use asset, leases		90.9
Liabilities and stockholders' equity:
Current portion of long-term debt		(0.1)
Lease liabilities		24.1
Long-term debt, net		(0.1)
Long-term lease liabilities		65.6
Accumulated deficit		$ 0.5
Balances without adoption of ASU 2016-02
Assets:
Property, plant and equipment, net	260.2
Right of use asset, leases	0.0
Liabilities and stockholders' equity:
Current portion of long-term debt	31.7
Lease liabilities	0.3
Long-term debt, net	882.6
Long-term lease liabilities	10.2
Accumulated deficit	(611.8)
Effect of Change Higher/(Lower) | Accounting Standards Update 2016-02
Assets:
Property, plant and equipment, net	(0.8)
Right of use asset, leases	95.8
Liabilities and stockholders' equity:
Current portion of long-term debt	(0.1)
Lease liabilities	20.3
Long-term debt, net	(0.1)
Long-term lease liabilities	74.4
Accumulated deficit	$ 0.5