Lines of Credit and Financing Arrangements (Outstanding Debt Obligations) (Details) - USD ($)	Dec. 31, 2016	Nov. 01, 2016	Dec. 31, 2015	May 31, 2010
Short-Term Debt:
Total short-term debt	$ 52,400,000		$ 204,100,000
Current maturities of long-term debt:
Capital lease obligations	800,000		1,200,000
Domestic credit facility	200,100,000		31,000,000
Long-Term Debt:
Capital lease obligations	15,000,000		15,600,000
Total long-term debt	615,700,000		506,000,000
Debt Issuance Cost, Gross, Noncurrent	(5,300,000)		(2,600,000)
Total debt	868,200,000		741,100,000
Domestic Credit Facility [Member]
Current maturities of long-term debt:
Domestic credit facility	0		30,000,000
Debt Issuance Costs, Gross, Current	(700,000)		(200,000)
Long-Term Debt:
Total long-term debt	256,000,000		293,000,000
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 350,000,000.0		$ 200,000,000.0
Current maturities of long-term debt:
Domestic credit facility	200,000,000		0
Long-Term Debt:
Total long-term debt	350,000,000		200,000,000
Asset Securitization Program [Member]
Short-Term Debt:
Total short-term debt	50,000,000		200,000,000
Foreign Obligations [Member]
Short-Term Debt:
Total short-term debt	$ 2,400,000		$ 4,100,000