Condensed Consolidating Financial Statements (Balance Sheets) (Details) - USD ($) $ in Millions	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
Current Assets:
Cash and cash equivalents	$ 46.1		$ 68.2	$ 60.7	$ 50.2
Accounts and notes receivable, net	580.9	$ 514.8	506.5
Inventories, net	501.5		484.2
Other assets	58.7		78.4
Total current assets	1,187.2		1,137.3
Property, plant and equipment, net	374.4		397.8
Goodwill	186.9		200.5
Investment in subsidiaries	0.0		0.0
Deferred income taxes	95.4		94.4
Other assets, net	66.9		61.5
Intercompany receivables (payables), net	0.0		0.0
Total assets	1,910.8		1,891.5
Current Liabilities:
Short-term debt	0.0		0.9
Current maturities of long-term debt	22.3		32.6
Accounts payable	371.6	$ 357.9	348.6
Accrued expenses	292.5		270.3
Income taxes (receivable) payable	4.1		2.1
Total current liabilities	690.5		654.5
Long-term debt	1,103.6		970.5
Post-retirement benefits, other than pensions	2.5		2.6
Pensions	70.7		84.5
Other liabilities	130.3		129.3
Total liabilities	1,997.6		1,841.4
Commitments and contingencies
Total stockholders' equity	(86.8)		50.1
Total liabilities and stockholders' equity	1,910.8		1,891.5
Eliminations [Member]
Current Assets:
Cash and cash equivalents	0.0		0.0	0.0	0.0
Accounts and notes receivable, net	0.0		0.0
Inventories, net	(4.7)		(3.4)
Other assets	(33.8)		(28.4)
Total current assets	(38.5)		(31.8)
Property, plant and equipment, net	(3.8)		(4.2)
Goodwill	0.0		0.0
Investment in subsidiaries	(2,122.7)		(1,622.9)
Deferred income taxes	(12.2)		(12.2)
Other assets, net	(1.4)		(1.5)
Intercompany receivables (payables), net	(102.8)		(102.8)
Total assets	(2,281.4)		(1,775.4)
Current Liabilities:
Short-term debt	0.0		0.0
Current maturities of long-term debt	0.0		0.0
Accounts payable	0.0		0.0
Accrued expenses	0.0		0.0
Income taxes (receivable) payable	(50.8)		(50.8)
Total current liabilities	(50.8)		(50.8)
Long-term debt	0.0		0.0
Post-retirement benefits, other than pensions	0.0		0.0
Pensions	0.0		0.0
Other liabilities	0.0		0.0
Total liabilities	(50.8)		(50.8)
Commitments and contingencies
Total stockholders' equity	(2,230.6)		(1,724.6)
Total liabilities and stockholders' equity	(2,281.4)		(1,775.4)
Parent [Member]
Current Assets:
Cash and cash equivalents	1.4		1.6	1.2	1.2
Accounts and notes receivable, net	0.0		0.0
Inventories, net	0.0		0.0
Other assets	3.3		16.2
Total current assets	4.7		17.8
Property, plant and equipment, net	0.0		0.0
Goodwill	0.0		0.0
Investment in subsidiaries	1,785.7		1,257.7
Deferred income taxes	6.6		3.9
Other assets, net	1.5		2.1
Intercompany receivables (payables), net	(1,140.1)		(559.3)
Total assets	658.4		722.2
Current Liabilities:
Short-term debt	0.0		0.0
Current maturities of long-term debt	21.9		29.4
Accounts payable	25.8		21.3
Accrued expenses	10.1		3.1
Income taxes (receivable) payable	(25.1)		(64.5)
Total current liabilities	32.7		(10.7)
Long-term debt	714.7		682.8
Post-retirement benefits, other than pensions	0.0		0.0
Pensions	0.0		0.0
Other liabilities	(2.2)		0.0
Total liabilities	745.2		672.1
Commitments and contingencies
Total stockholders' equity	(86.8)		50.1
Total liabilities and stockholders' equity	658.4		722.2
Guarantor Subsidiaries [Member]
Current Assets:
Cash and cash equivalents	24.0		28.0	22.4	17.1
Accounts and notes receivable, net	54.7		35.3
Inventories, net	403.4		355.7
Other assets	35.2		23.1
Total current assets	517.3		442.1
Property, plant and equipment, net	262.3		257.6
Goodwill	166.1		134.9
Investment in subsidiaries	337.5		365.8
Deferred income taxes	75.5		69.1
Other assets, net	49.8		41.3
Intercompany receivables (payables), net	1,113.4		554.7
Total assets	2,521.9		1,865.5
Current Liabilities:
Short-term debt	0.0		0.0
Current maturities of long-term debt	0.1		2.9
Accounts payable	242.9		228.0
Accrued expenses	240.8		209.4
Income taxes (receivable) payable	31.4		56.5
Total current liabilities	515.2		496.8
Long-term debt	11.6		11.7
Post-retirement benefits, other than pensions	2.5		2.6
Pensions	61.8		74.7
Other liabilities	124.4		120.6
Total liabilities	715.5		706.4
Commitments and contingencies
Total stockholders' equity	1,806.4		1,159.1
Total liabilities and stockholders' equity	2,521.9		1,865.5
Non-Guarantor Subsidiaries [Member]
Current Assets:
Cash and cash equivalents	20.7		38.6	$ 37.1	$ 31.9
Accounts and notes receivable, net	526.2		471.2
Inventories, net	102.8		131.9
Other assets	54.0		67.5
Total current assets	703.7		709.2
Property, plant and equipment, net	115.9		144.4
Goodwill	20.8		65.6
Investment in subsidiaries	(0.5)		(0.6)
Deferred income taxes	25.5		33.6
Other assets, net	17.0		19.6
Intercompany receivables (payables), net	129.5		107.4
Total assets	1,011.9		1,079.2
Current Liabilities:
Short-term debt	0.0		0.9
Current maturities of long-term debt	0.3		0.3
Accounts payable	102.9		99.3
Accrued expenses	41.6		57.8
Income taxes (receivable) payable	48.6		60.9
Total current liabilities	193.4		219.2
Long-term debt	377.3		276.0
Post-retirement benefits, other than pensions	0.0		0.0
Pensions	8.9		9.8
Other liabilities	8.1		8.7
Total liabilities	587.7		513.7
Commitments and contingencies
Total stockholders' equity	424.2		565.5
Total liabilities and stockholders' equity	$ 1,011.9		$ 1,079.2