Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies - Narrative (Details) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($) $ / shares	Sep. 30, 2017 USD ($) $ / shares	Sep. 30, 2018 USD ($) segment $ / shares	Sep. 30, 2017 USD ($) $ / shares	Dec. 31, 2017 USD ($)	Jan. 01, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of reportable segments | segment			2
Depreciation and amortization			$ 76.1	$ 82.6
Net income (loss)	$ 15.9	$ 47.1	$ 97.9	$ 133.5
Net income (loss) (in dollars per shares) | $ / shares	$ 0.24	$ 0.70	$ 1.46	$ 1.96
Adjustment to retained earnings as a result of adoption of new accounting guidance	$ 625.4		$ 625.4		$ 573.1
Adjustment to other liabilities as a result of adoption of new accounting guidance	(280.3)		(280.3)		(169.3)
Adjustment to deferred income taxes as a result of adoption of new accounting guidance	(543.6)		(543.6)		$ (556.5)
Service Life | Machinery and Equipment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Depreciation and amortization	(7.6)		(16.5)
Net income (loss)	$ 5.8		$ 12.7
Net income (loss) (in dollars per shares) | $ / shares	$ 0.09		$ 0.19
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Payment terms			30 days
Minimum | Machinery and Equipment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment, useful life					3 years
Minimum | Service Life | Machinery and Equipment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment, useful life			5 years
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Payment terms			60 days
Contract term			7 years
Maximum | Machinery and Equipment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment, useful life					10 years
Maximum | Service Life | Machinery and Equipment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment, useful life			25 years
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income (loss)	$ 0.4		$ 0.7
Adjustment to retained earnings as a result of adoption of new accounting guidance	3.2		3.2			$ 2.5
Adjustment to other liabilities as a result of adoption of new accounting guidance	4.1		4.1			(3.2)
Adjustment to deferred income taxes as a result of adoption of new accounting guidance	$ 0.9		$ 0.9			$ (0.7)