Debt Schedule of Outstanding Debt (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Notes Payable to Bank	$ 0.0	$ 3.9
Debt and Lease Obligation	338.8	355.1
Unamortized Debt Issuance Costs	(3.8)	(4.7)
Long-Term Debt	307.5	328.1
Current Portion of Long-Term Debt	31.3	27.0
Current Maturities of Finance Lease Obligations	0.2
Letters of Credit Outstanding, Amount	3.3
Commitment fees on unused lines of credit	$ 0.5
Weighted average interest rate at end of period	5.30%
Debt, Weighted Average Interest Rate, net of Currency Swap Contract	4.40%
Line of Credit [Member]
Debt Instrument [Line Items]
Debt and Lease Obligation	$ 40.0	53.0
Less: Current Maturities of Credit Facility Borrowings, Net of Debt Issuance Costs	(31.3)	(27.0)
Current Portion of Long-Term Debt	30.0
Debt Instrument, Unamortized Debt Issuance Costs, Current Portion, net	1.1
Outstanding Borrowings	40.0
Secured Borrowings [Member]
Debt Instrument [Line Items]
Debt and Lease Obligation	2.4	2.4
Finance Lease Liabilities [Member]
Debt Instrument [Line Items]
Debt and Lease Obligation	0.2	0.5
Revolving Credit Facility
Debt Instrument [Line Items]
Debt Instrument, Unused Borrowing Capacity, Amount	156.7
Long-term Debt, Additional Repayments of Principal in Next Twelve Months	30.0
Long-term Debt, Current Maturities	30.0
Bonds
Debt Instrument [Line Items]
Debt and Lease Obligation	300.0	$ 300.0
Outstanding Borrowings	$ 300.0

Debt, Current, Net Of Unamortized Debt Issuance Costs

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Amount of unamortized debt issuance costs, current portion, net

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Amount of unamortized debt issuance costs, noncurrent portion

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Weighted average interest rate of debt outstanding, net of currency swap contract.

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Long-term Debt, Additional Repayments of Principal in Next Twelve Months

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Amount of short-term and long-term debt and lease obligation.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Weighted average interest rate of debt outstanding.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of the fee for available but unused credit capacity under the credit facility.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, the carrying value as of the balance sheet date of notes payable to banks, excluding mortgage notes, initially due beyond one year or beyond the operating cycle if longer.

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