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Requirement for minimum leverage ratio required to pay dividends or repurchase stock under the debt agreement.

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

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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Carrying value as of the balance sheet date of the portion of long-term, collateralized debt obligations due within one year or the operating cycle, if longer. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Note 8 - Debt (Details Textual) - USD ($) $ in Millions		3 Months Ended	6 Months Ended	9 Months Ended
Note 8 - Debt (Details Textual) - USD ($) $ in Millions	Apr. 05, 2021	Jun. 30, 2021	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Payment for Debt Extinguishment or Debt Prepayment Cost				$ 8.4	$ (0.0)
Write off of Deferred Debt Issuance Cost				11.3	$ 0.0
Secured Debt, Current				$ 0.6
Debt, Weighted Average Interest Rate, Net of Currency Swap Contract				0.40%
Debt Including Related Cross-currency Swap Instrument [Member]
Debt, Weighted Average Interest Rate				1.30%
The 2021 Credit Agreement [Member]
Debt Instrument, Collateral, Percentage of Stock of First Tier Foreign Subsidiaries	65.00%
Debt Instrument, Dividend Payments Allowed Per Quarter	$ 7.5
Debt Instrument, Covenant, Adjusted EBITDA, Maximum	3.50
Debt Instrument, Covenant, Minimum Permitted Acquisition, Alternative Requirements for Indebtedness to EBITDA Ratio	$ 50.0
Debt Instrument, Covenant, Adjusted EBITDA to Interest Expense Ratio, Minimum	3.00
Debt Instrument, Covenant, Minimum Leverage Ratio for Dividends or Repurchase of Stock	2.50
Debt Instrument, Restrictions, Maximum Dividends Payout or Repurchase of Stock	$ 60.0
Long-term Debt, Current Maturities, Total				$ 3.1
Letters of Credit Outstanding, Amount				2.9
The 2021 Credit Agreement [Member] \| LIBOR on Eurocurrency Liabilities [Member]
Debt Instrument, Variable Rate Floor	0.00%
The 2021 Credit Agreement [Member] \| Fed Funds Effective Rate Overnight Index Swap Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	0.50%
The 2021 Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Variable Rate Floor	1.00%
The 2021 Credit Agreement [Member] \| Minimum [Member]
Debt Instrument, Other Restricted Payments Allowed Per Quarter	$ 60.0
The 2021 Credit Agreement [Member] \| Minimum [Member] \| LIBOR on Eurocurrency Liabilities [Member]
Debt Instrument, Basis Spread on Variable Rate	1.10%
The 2021 Credit Agreement [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	0.10%
The 2021 Credit Agreement [Member] \| Maximum [Member] \| LIBOR on Eurocurrency Liabilities [Member]
Debt Instrument, Basis Spread on Variable Rate	1.70%
The 2021 Credit Agreement [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	0.70%
The 2021 Credit Agreement [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 450.0
Line of Credit Facility, Additional Borrowings Option	$ 275.0
Long-term Debt, Gross				168.0		$ 10.0
Debt Instrument, Unused Borrowing Capacity, Amount				279.1
Line of Credit Facility, Commitment Fee Amount				0.6
The 2021 Credit Agreement [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Line of Credit Facility, Commitment Fee Percentage	0.15%
The 2021 Credit Agreement [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Line of Credit Facility, Commitment Fee Percentage	0.30%
The 2021 Credit Agreement [Member] \| Term Loan [Member]
Debt Instrument, Face Amount	$ 100.0
Long-term Debt, Gross				99.4		0.0
Senior Unsecured Notes [Member]
Debt Instrument, Amount Redeemed		$ 300.0	$ 300.0
Debt Instrument, Interest Rate, Stated Percentage		5.625%	5.625%
Write off of Deferred Debt Issuance Cost		$ 2.9
Long-term Debt, Gross				$ 0.0		$ 300.0
Senior Unsecured Notes [Member] \| Debt Redemption Call Premium [Member]
Payment for Debt Extinguishment or Debt Prepayment Cost			$ 8.4