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Debt, Interest Income, Expense and Other Finance Costs - Summary of Debt (Details) € in Millions	Dec. 31, 2019 USD ($)	Dec. 31, 2019 EUR (€)	Jul. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Debt
Finance leases	$ 18,700,000
Finance leases				$ 13,800,000
Total debt	628,800,000			701,000,000.0
Current maturities of long-term debt	54,100,000			41,100,000
Long-term debt	574,700,000			659,900,000
Other
Debt
Long-term debt	39,500,000			2,300,000
Line of Credit \| Credit Facility
Debt
Long-term debt	55,000,000.0			170,000,000.0
Senior Notes \| Term Loans
Debt
Long-term debt	515,600,000		$ 525,000,000.0	$ 514,800,000
Secured Borrowing
Debt
Long-term debt	$ 37,300,000	€ 33.6