Borrowings and Lines of Credit - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year	$ 0.0
Long-term Debt, Maturities, Repayments of Principal in Year Two	0.0
Long-term Debt, Maturities, Repayments of Principal in Year Three	172.5
Long-term borrowings [Abstract]
Long-term debt	158.1	$ 192.6
Less: current maturities	0.0	0.0
Long-term debt (noncurrent)	158.1	192.6
Term Loan and Revolving Credit Facility Due January 2019 [Member]
Long-term borrowings [Abstract]
Less: current maturities	0.0	0.0
Long-term debt (noncurrent)	$ 9.0	50.7
Convertible Debt \| Convertible Notes Due Twenty Twenty One [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	17250000000.00%
Long-term Debt, Maturities, Repayments of Principal in Year Four	$ 9.0
Long-term borrowings [Abstract]
Convertible Debt	149.1	141.9
Line of Credit \| Credit Facility Due October 11, 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Year Five	0.0
Long-term borrowings [Abstract]
Long-term Line of Credit	$ 9.0
Line of Credit \| Term Loan and Revolving Credit Facility Due January 2019 [Member]
Long-term borrowings [Abstract]
Long-term Line of Credit		$ 50.7

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Contractual interest rate for funds borrowed, under the debt agreement.

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

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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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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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