Employee Benefits - Benefit Plans and Related Amounts Recorded in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Projected benefit obligation	$ 52,503	$ 44,890	$ 45,450	$ 38,400
Pension plan assets at fair value	(23,444)	(19,460)	(18,475)	$ (14,465)
Funded status – shortfall	29,059	25,430	26,975
Amounts recorded in the Consolidated Balance Sheets for the plans
Other liabilities — accrued pension obligation	29,059	25,430	26,975
Stockholders’ equity — deferred actuarial loss	$ (8,584)	$ (5,738)	$ (5,861)
Future long-term rate of return on plan assets	2.04%
Weighted average amortization period	14 years
Future amortization expense of unrecognized losses	$ (500)