Borrowings (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Long-term borrowings
Long-term debt	$ 258.8	$ 156.8
Less: current maturities	0.0	0.0
Long-term portion	258.8	156.8
Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year	0.0
Long-term Debt, Maturities, Repayments of Principal in Year Two	172.5
Long-term Debt, Maturities, Repayments of Principal in Year Three	100.0
Convertible Debt \| Convertible Notes Due Twenty Twenty One
Long-term borrowings
Convertible Notes Payable	158.8	156.8
Long-term Debt, Maturities, Repayments of Principal in Year Four	0.0
Debt Instrument, Unamortized Discount	13.7	15.7
Line of Credit \| Credit Facility due October 11, 2022
Long-term borrowings
Long-term Line of Credit	100.0	$ 0.0
Long-term Debt, Maturities, Repayments of Principal in Year Five	$ 0.0

Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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