Represents the term (period to maturity) of held-to-maturity securities.

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Represents the amount of interest rate swap amortized to interest expense during the period.

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No definition available.

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Represents the amount of reduction to interest expense recorded during the period as a result of interest rate swap de-designated as cash flow hedge.

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No definition available.

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Represents the balance of interest rate swaps remaining in other comprehensive income, which amount will be amortized quarterly to interest expense.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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- Definition

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

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

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Nominal or face amount used to calculate payment on derivative.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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Note 9 - Fair Value Measurement (Details Textual) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Nov. 30, 2019	May 31, 2018
Derivative Liability, Notional Amount						$ 150.0
Interest Rate Swap De-designated as Cash Flow Hedge, Reduction to Interest Expense	$ 0.8
Interest Rate Swaps, Balance of Swaps Remaining in Other Comprehensive Income, Amount to Be Amortized Quarterly to Interest Expense	5.4	$ 5.4
Interest Rate Swap, Amortization to Interest Expense	$ 0.7	$ 1.5
The 2.75% Convertible Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	2.75%	2.75%	2.75%	2.75%	2.75%
Debt Instrument, Convertible, Carrying Amount of Equity Component	$ 26.2	$ 26.2	$ 29.7	$ 33.1	$ 27.9
US Treasury and Government [Member] \| Minimum [Member]
Debt Securities, Held-to-maturity, Term (Year)		1 year
US Treasury and Government [Member] \| Maximum [Member]
Debt Securities, Held-to-maturity, Term (Year)		5 years
Commodity Contract [Member]
Derivative, Notional Amount	4.9	$ 4.9
Unrealized Gain (Loss) on Derivatives and Commodity Contracts, Total	$ 1.2	$ 1.3
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		2.76%