Short and Long-Term Debt - Long-Term Debt Additional Information (Detail)		12 Months Ended
	Jan. 22, 2016 GBP (£)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Maturity obligation, year one		$ 20,000,000.0
Maturity obligation, year two		0
Maturity obligation, year three		221,600,000
Maturity obligation, year four		8,300,000
Maturity obligation, year 5		8,300,000
Maturity obligation, thereafter		50,100,000
Bank guarantees and letters of credit, outstanding		9,000,000.0
Restricted Cash and Cash Equivalents		$ 400,000	$ 300,000
Revolving Credit Facility
Debt Instrument [Line Items]
Weighted average revolver interest rate		1.15%
Unused senior revolving credit facility		$ 385,500,000
Line of credit, maximum borrowing capacity		600,000,000.0
Bank guarantees and letters of credit, outstanding		1,300,000
Multi-currency Notes Due in 2031
Debt Instrument [Line Items]
Notes payable, principal amount	£ 54,900,000	75,100,000
Notes payable, annual repayment installments	£ 6,100,000	$ 8,300,000
Notes payable, interest rate		3.40%
Minimum fixed charges coverage ratio (not less than)		1.50
Consolidated leverage ratio (not to exceed)		3.50
Federal Funds Open Rate | Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Daily Libor Rate | Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate		1.00%
Minimum | BASE or LIBOR | Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate		0.00%
Maximum | BASE or LIBOR | Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate		1.75%