Retirement Plans - Schedule of Costs of Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Defined Contribution Plan Disclosure
Expenses associated with contributions made	$ 529	$ 12
United States
Defined Contribution Plan Disclosure
Expenses associated with contributions made	364	(138)
Canada
Defined Contribution Plan Disclosure
Expenses associated with contributions made	46	39
United Kingdom
Defined Contribution Plan Disclosure
Expenses associated with contributions made	$ 119	$ 111