Retirement Plans - Information About Plan Assets (Details) - Pension Plan - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
United States
Defined Benefit Plan Disclosure
Fair value of plan assets	$ 4,767	$ 4,459	$ 4,360
United States | Cash and cash equivalents
Defined Benefit Plan Disclosure
Fair value of plan assets	171	399
United States | Total fixed income funds
Defined Benefit Plan Disclosure
Fair value of plan assets	667	1,440
United States | Corporate bonds
Defined Benefit Plan Disclosure
Fair value of plan assets	667	1,440
United States | Total mutual funds and equities
Defined Benefit Plan Disclosure
Fair value of plan assets	3,929	2,620
United States | Mutual funds
Defined Benefit Plan Disclosure
Fair value of plan assets	802	713
United States | Equity securities
Defined Benefit Plan Disclosure
Fair value of plan assets	3,127	1,907
United Kingdom
Defined Benefit Plan Disclosure
Fair value of plan assets	8,409	7,975	$ 7,290
United Kingdom | Cash and cash equivalents
Defined Benefit Plan Disclosure
Fair value of plan assets	339	348
United Kingdom | Bonds
Defined Benefit Plan Disclosure
Fair value of plan assets	3,491	3,410
United Kingdom | Other
Defined Benefit Plan Disclosure
Fair value of plan assets	757	1,116
United Kingdom | Equity securities
Defined Benefit Plan Disclosure
Fair value of plan assets	$ 3,822	$ 3,101