Employee Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Retirement Benefits [Abstract]
Service cost	$ 261	$ 1,353	$ 319
Interest cost	601	468	537
Net periodic benefit cost	$ 862	$ 1,821	$ 856