Long-Term Debt - Summary (Details) $ in Millions	Jun. 30, 2022 USD ($)	Jun. 30, 2022 AUD ($)	Dec. 31, 2021 USD ($)
Long Term Debt
Total long-term debt	$ 1,486,000,000		$ 1,474,000,000
Less: current portion	(78,500,000)		(82,000,000.0)
Net long-term debt	1,407,500,000		1,392,000,000
U.S. credit agreement — revolving credit line
Long Term Debt
Total long-term debt	0		0
U.K. credit agreement — revolving credit line
Long Term Debt
Total long-term debt	0		0
U.K. credit agreement — overdraft line of credit
Long Term Debt
Total long-term debt	0		0
3.50% senior subordinated notes due 2025
Long Term Debt
Total long-term debt	$ 545,400,000		544,700,000
Interest rate (as a percent)	3.50%	3.50%
3.75% senior subordinated notes due 2029
Long Term Debt
Total long-term debt	$ 494,700,000		494,300,000
Interest rate (as a percent)	3.75%	3.75%
Australia capital loan agreement
Long Term Debt
Total long-term debt	$ 23,300,000		26,600,000
Australia working capital loan agreement
Long Term Debt
Total long-term debt	6,900,000	$ 10.0	0
Mortgage facilities
Long Term Debt
Total long-term debt	366,900,000		353,800,000
Other
Long Term Debt
Total long-term debt	$ 48,800,000		$ 54,600,000