Postretirement Benefit Plans - Company's Asset Allocations for its U.K. Pension Plans by Asset Category (Detail) - United Kingdom [Member] - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Total	$ 16,091	$ 15,163	$ 27,464
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	15,331	14,486
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	760	677
Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	1,308	1,448
Cash [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	1,308	1,448
Pooled Pension Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	1,017	1,688
Pooled Pension Funds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	1,017	1,688
Pooled Fixed Pension Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	12,860	11,350
Pooled Fixed Pension Funds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	12,860	11,350
Real Estate Pooled Pension Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	146
Real Estate Pooled Pension Funds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	146
Insurance Contracts [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	760	677
Insurance Contracts [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	$ 760	$ 677