Condensed Consolidating Financial Statements (Balance Sheets) (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 36,400,000	$ 46,300,000	$ 39,400,000	$ 68,200,000
Short-term Investments	1,800,000	0
Accounts and notes receivable, net	718,800,000	472,700,000
Inventories, net	630,200,000	509,800,000
Other assets	56,700,000	60,600,000
Total current assets	1,443,900,000	1,089,400,000
Property, plant and equipment, net	418,000,000.0	408,300,000
Right-of-use assets from operating leases	166,200,000	0
Goodwill	186,600,000	186,600,000
Investment in subsidiaries	0	0
Deferred income taxes	49,200,000	67,000,000.0
Other assets, net	76,500,000	65,900,000
Intercompany receivables (payables), net	0	0
Total assets	2,340,400,000	1,817,200,000
Current Liabilities:
Short-term debt		0
Current maturities of long-term debt	311,000,000.0	300,800,000
Current operating lease liabilities	49,600,000	0
Accounts payable	473,600,000	433,300,000
Accrued expenses	240,800,000	272,300,000
Income taxes (receivable) payable	0	2,100,000
Total current liabilities	1,075,000,000.0	1,008,500,000
Long-term debt	1,155,800,000	740,500,000
Long-term operating lease liabilities	117,600,000	0
Pensions	79,600,000	82,800,000
Other liabilities	129,900,000	135,000,000.0
Total liabilities	2,557,900,000	1,966,800,000
Commitments and contingencies
Total stockholders' (deficit) equity	(217,500,000)	(149,600,000)
Total liabilities and stockholders' deficit	2,340,400,000	1,817,200,000
Eliminations [Member]
Current Assets:
Cash and cash equivalents	0	0	0	0
Accounts and notes receivable, net	0	0
Inventories, net	(2,100,000)	(5,500,000)
Other assets	(34,400,000)	(33,600,000)
Total current assets	(36,500,000)	(39,100,000)
Property, plant and equipment, net	0	(3,600,000)
Right-of-use assets from operating leases	0
Goodwill	0	0
Investment in subsidiaries	(2,152,700,000)	(1,669,200,000)
Deferred income taxes	(12,300,000)	(12,200,000)
Other assets, net	14,200,000	(1,500,000)
Intercompany receivables (payables), net	(120,000,000.0)	(102,900,000)
Total assets	(2,307,300,000)	(1,828,500,000)
Current Liabilities:
Short-term debt		0
Current maturities of long-term debt	0	0
Current operating lease liabilities	0
Accounts payable	0	0
Accrued expenses	0	0
Income taxes (receivable) payable	(50,800,000)	(50,800,000)
Total current liabilities	(50,800,000)	(50,800,000)
Long-term debt	0	0
Long-term operating lease liabilities	0
Pensions	0	0
Other liabilities	0	0
Total liabilities	(50,800,000)	(50,800,000)
Commitments and contingencies
Total stockholders' (deficit) equity	(2,256,500,000)	(1,777,700,000)
Total liabilities and stockholders' deficit	(2,307,300,000)	(1,828,500,000)
Parent [Member]
Current Assets:
Cash and cash equivalents	1,900,000	1,800,000	1,600,000	1,600,000
Short-term Investments	0
Accounts and notes receivable, net	0	0
Inventories, net	0	0
Other assets	3,500,000	3,300,000
Total current assets	5,400,000	5,100,000
Property, plant and equipment, net	0	0
Right-of-use assets from operating leases	0
Goodwill	0	0
Investment in subsidiaries	1,532,300,000	1,311,900,000
Deferred income taxes	(11,100,000)	1,400,000
Other assets, net	1,700,000	1,500,000
Intercompany receivables (payables), net	(587,000,000.0)	(715,500,000)
Total assets	941,300,000	604,400,000
Current Liabilities:
Short-term debt		0
Current maturities of long-term debt	14,400,000	29,400,000
Current operating lease liabilities	0
Accounts payable	30,000,000.0	25,500,000
Accrued expenses	6,500,000	12,100,000
Income taxes (receivable) payable	(24,700,000)	(38,500,000)
Total current liabilities	26,200,000	28,500,000
Long-term debt	1,132,400,000	724,900,000
Long-term operating lease liabilities	0
Pensions	0	0
Other liabilities	200,000	600,000
Total liabilities	1,158,800,000	754,000,000.0
Commitments and contingencies
Total stockholders' (deficit) equity	(217,500,000)	(149,600,000)
Total liabilities and stockholders' deficit	941,300,000	604,400,000
Guarantor Subsidiaries [Member]
Current Assets:
Cash and cash equivalents	22,300,000	15,400,000	22,600,000	28,000,000.0
Short-term Investments	0
Accounts and notes receivable, net	75,900,000	44,300,000
Inventories, net	552,300,000	411,400,000
Other assets	35,700,000	36,200,000
Total current assets	686,200,000	507,300,000
Property, plant and equipment, net	362,900,000	293,300,000
Right-of-use assets from operating leases	142,200,000
Goodwill	166,100,000	166,100,000
Investment in subsidiaries	570,200,000	357,800,000
Deferred income taxes	49,500,000	54,400,000
Other assets, net	54,200,000	48,100,000
Intercompany receivables (payables), net	589,000,000.0	675,800,000
Total assets	2,620,300,000	2,102,800,000
Current Liabilities:
Short-term debt		0
Current maturities of long-term debt	5,700,000	2,800,000
Current operating lease liabilities	42,900,000
Accounts payable	393,300,000	295,700,000
Accrued expenses	193,700,000	213,800,000
Income taxes (receivable) payable	34,100,000	40,600,000
Total current liabilities	669,700,000	552,900,000
Long-term debt	21,800,000	15,000,000.0
Long-term operating lease liabilities	100,200,000
Pensions	71,800,000	75,100,000
Other liabilities	122,600,000	126,400,000
Total liabilities	986,100,000	769,400,000
Commitments and contingencies
Total stockholders' (deficit) equity	1,634,200,000	1,333,400,000
Total liabilities and stockholders' deficit	2,620,300,000	2,102,800,000
Non-Guarantor Subsidiaries [Member]
Current Assets:
Cash and cash equivalents	12,200,000	29,100,000	$ 15,200,000	$ 38,600,000
Short-term Investments	1,800,000
Accounts and notes receivable, net	642,900,000	428,400,000
Inventories, net	80,000,000.0	103,900,000
Other assets	51,900,000	54,700,000
Total current assets	788,800,000	616,100,000
Property, plant and equipment, net	55,100,000	118,600,000
Right-of-use assets from operating leases	24,000,000.0
Goodwill	20,500,000	20,500,000
Investment in subsidiaries	50,200,000	(500,000)
Deferred income taxes	23,100,000	23,400,000
Other assets, net	6,400,000	17,800,000
Intercompany receivables (payables), net	118,000,000.0	142,600,000
Total assets	1,086,100,000	938,500,000
Current Liabilities:
Short-term debt		0
Current maturities of long-term debt	290,900,000	268,600,000
Current operating lease liabilities	6,700,000
Accounts payable	50,300,000	112,100,000
Accrued expenses	40,600,000	46,400,000
Income taxes (receivable) payable	41,400,000	50,800,000
Total current liabilities	429,900,000	477,900,000
Long-term debt	1,600,000	600,000
Long-term operating lease liabilities	17,400,000
Pensions	7,800,000	7,700,000
Other liabilities	7,100,000	8,000,000.0
Total liabilities	463,800,000	494,200,000
Commitments and contingencies
Total stockholders' (deficit) equity	622,300,000	444,300,000
Total liabilities and stockholders' deficit	$ 1,086,100,000	$ 938,500,000