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, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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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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 borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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The leverage ratio of a debt instrument.

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Represents interest expense excluding earn out interest.

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Note 15 - Debt (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Note 15 - Debt (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 08, 2020	Aug. 15, 2019
Interest Payable, Current	$ 20,700	$ 19,000
Interest Expense Excluding Earn Out Interest	138,300	125,700	$ 128,200
Long-term Debt, Gross	3,150,000	2,650,000
Letters of Credit Outstanding, Amount	5,400	4,800
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity					$ 1,000,000
Debt Instrument, Leverage Ratio					3.5
Line of Credit Facility, Remaining Borrowing Capacity	944,600	$ 500,200
Long-term Line of Credit, Total	0
Repayments of Lines of Credit	$ 50,000
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument, Interest Rate, Stated Percentage					1.00%
Debt Instrument, Leverage Ratio					4.0
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument, Interest Rate, Stated Percentage					1.625%
Debt Instrument, Leverage Ratio					4.25
The 3.625% Senior Note [Member]
Debt Instrument, Face Amount				$ 500,000
Debt Instrument, Interest Rate, Stated Percentage	3.625%			3.625%
Debt Instrument, Unamortized Discount, Total	$ 10,700			$ 5,200
Debt Issuance Costs, Net, Total				$ 5,700
Commitment Fee [Member] \| Minimum [Member]
Debt Instrument, Interest Rate, Stated Percentage					0.08%
Commitment Fee [Member] \| Maximum [Member]
Debt Instrument, Interest Rate, Stated Percentage					0.20%