Average borrowings outstanding during the period, both short and long term.

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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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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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The average effective interest rate during the reporting period.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Amount of the cost of borrowed funds accounted for as interest expense.

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The net amount of operating interest income (expense).

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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 of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Debt (Narrative) (Details)		3 Months Ended
Debt (Narrative) (Details)	Mar. 31, 2022 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 GBP (£)	Dec. 31, 2021 USD ($)	May 30, 2018 USD ($)
Debt Instrument [Line Items]
Average borrowings outstanding		$ 665,000,000	$ 512,100,000
Weighted average interest rate		4.30%	5.00%
Interest Expense, Net		$ (10,702,000)	$ (7,558,000)
Interest expense		11,417,000	8,448,000
5.75% Unsecured Notes maturing in 2026 [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 3,000,000	$ 3,000,000			$ 3,200,000
Interest rate	5.75%	5.75%		5.75%	5.75%
Fair value of debt instrument	$ 411,100,000	$ 411,100,000			$ 417,500,000
Commercial note with Truist Bank maturing in 2031 [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	100,000	100,000			100,000
Five-Year Credit Agreement maturing in 2023 [Member]
Debt Instrument [Line Items]
Credit facility current borrowing capacity						$ 300,000,000
Line of credit facility outstanding	170,918,000	170,918,000			$ 209,643,000
USD $200 million portion of revolver [Member]
Debt Instrument [Line Items]
Line of credit facility outstanding	$ 100,000,000	$ 100,000,000
Multicurrency $100 million portion of revolver [Member]
Debt Instrument [Line Items]
Line of credit facility outstanding \| £				£ 54,000,000
Pinnacle Bank Term Loan maturing in 2024 [Member]
Debt Instrument [Line Items]
Interest rate	4.15%	4.15%		4.15%
Minimum [Member] \| Commercial note with Truist Bank maturing in 2031 [Member]
Debt Instrument [Line Items]
Interest rate	1.85%	1.85%		1.85%
Minimum [Member] \| Five-Year Credit Agreement maturing in 2023 [Member]
Debt Instrument [Line Items]
Interest rate	1.61%	1.61%		1.61%
Minimum [Member] \| Other Indebtedness [Member]
Debt Instrument [Line Items]
Interest rate	0.00%	0.00%		0.00%
Maximum [Member] \| Commercial note with Truist Bank maturing in 2031 [Member]
Debt Instrument [Line Items]
Interest rate	1.91%	1.91%		1.91%
Maximum [Member] \| Five-Year Credit Agreement maturing in 2023 [Member]
Debt Instrument [Line Items]
Interest rate	3.75%	3.75%		3.75%
Maximum [Member] \| Other Indebtedness [Member]
Debt Instrument [Line Items]
Interest rate	16.00%	16.00%		16.00%
London Interbank Offered Rate (LIBOR) [Member] \| USD $200 million portion of revolver [Member]
Debt Instrument [Line Items]
Applicable interest rate margin	1.50%
Prime Rate [Member] \| USD $200 million portion of revolver [Member]
Debt Instrument [Line Items]
Applicable interest rate margin	0.50%
Sterling Overnight Interbank Average Rate (SONIA) [Member] \| Multicurrency $100 million portion of revolver [Member]
Debt Instrument [Line Items]
Applicable interest rate margin	1.50%
Securities Subject to Mandatory Redemption [Member] \| Graham Healthcare Group [Member]
Debt Instrument [Line Items]
Interest expense		$ 3,400,000	$ 1,100,000