Debt (Narrative) (Details)			3 Months Ended		6 Months Ended
	Jul. 28, 2023 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 GBP (£)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Average borrowings outstanding			$ 742,100,000	$ 638,300,000	$ 738,300,000	$ 648,800,000
Weighted average interest rate			6.00%	4.70%	5.90%	4.50%
Interest Expense, Net			$ (10,226,000)	$ (15,277,000)	$ (23,316,000)	$ (25,979,000)
Interest expense			11,774,000	15,973,000	26,068,000	27,390,000
5.75% Unsecured Notes maturing in 2026 [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs		$ 2,100,000	$ 2,100,000		$ 2,100,000			$ 2,500,000
Interest rate		5.75%	5.75%		5.75%		5.75%	5.75%
Fair value of debt instrument		$ 395,100,000	$ 395,100,000		$ 395,100,000			$ 395,100,000
Five-Year Credit Agreement maturing in 2027 [Member]
Debt Instrument [Line Items]
Credit facility current borrowing capacity		300,000,000	300,000,000		300,000,000
Line of credit facility outstanding		188,136,000	188,136,000		188,136,000			200,236,000
USD revolving credit facility borrowings [Member]
Debt Instrument [Line Items]
Line of credit facility outstanding		125,000,000	125,000,000		125,000,000
GBP revolving credit facility borrowings [Member]
Debt Instrument [Line Items]
Line of credit facility outstanding | £							£ 50,000,000
Commercial note with Truist Bank maturing in 2031 - $24.75 million [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs		100,000	100,000		100,000			100,000
Commercial note with Truist Bank maturing in 2032 - $27.2 million [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs		$ 100,000	100,000		100,000			$ 100,000
Term Loan A maturing in 2027 - $150 million [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Loans Payable to Bank	$ 150,000,000
Debt Instrument, Periodic Payment, Principal	$ 1,875,000
Secured Overnight Financing Rates (SOFR) [Member] | USD revolving credit facility borrowings [Member]
Debt Instrument [Line Items]
Applicable interest rate margin		1.375%
Secured Overnight Financing Rates (SOFR) [Member] | Term Loan A maturing in 2027 - $150 million [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Applicable interest rate margin	1.75%
Prime Rate [Member] | USD revolving credit facility borrowings [Member]
Debt Instrument [Line Items]
Applicable interest rate margin		0.375%
Sterling Overnight Interbank Average Rate (SONIA) [Member] | GBP revolving credit facility borrowings [Member]
Debt Instrument [Line Items]
Applicable interest rate margin		1.375%
Securities Subject to Mandatory Redemption [Member] | Graham Healthcare Group [Member]
Debt Instrument [Line Items]
Interest expense			$ (1,200,000)	$ 8,000,000	$ 300,000	$ 11,400,000