Retirement Plans - Schedule of Benefit Obligation, Fair Value of Assets, and Funded Status of the Plans (Details) - Pension Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
United States
Change in benefit obligation
Benefit obligation at beginning of year	$ 16,717	$ 18,783
Interest cost	648	622
Actuarial loss (gain)	400	(1,249)
Benefits paid	(840)	(1,439)
Settlements	(9,116)	0
Benefit obligation at end of year	7,809	16,717
Change in plan asset
Fair value of assets at beginning of year	12,468	14,892
Actual gain (loss) on plan assets	1,298	(985)
Employer contribution	550	0
Benefits paid	(840)	(1,439)
Settlements	(9,116)	0
Fair value of assets at end of year	4,360	12,468
Funded status at end of year	(3,449)	(4,249)
Amount recognized in the consolidated balance sheet consists of:
Other long-term liabilities	(3,449)	(4,249)
Amounts recognized in accumulated other comprehensive income consists of:
Net loss	1,893	4,406
United Kingdom
Change in benefit obligation
Benefit obligation at beginning of year	7,750	8,335
Interest cost	221	194
Actuarial loss (gain)	1,142	(201)
Benefits paid	(326)	(292)
Foreign currency exchange rate changes	314	(475)
Benefit obligation at end of year	9,101	7,750
Change in plan asset
Fair value of assets at beginning of year	6,347	6,904
Actual gain (loss) on plan assets	697	(144)
Employer contribution	314	271
Benefits paid	(326)	(292)
Foreign currency exchange rate changes	258	(392)
Fair value of assets at end of year	7,290	6,347
Funded status at end of year	(1,811)	(1,403)
Amount recognized in the consolidated balance sheet consists of:
Other long-term liabilities	(1,811)	(1,403)
Amounts recognized in accumulated other comprehensive income consists of:
Net loss	1,641	1,116
Prior service cost	172	208
Defined benefit plan, comprehensive (income) loss	$ 1,813	$ 1,324