Employee Benefit Plans - Schedule of Reconciliation of Balances in AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Net gain (loss) arising during period	$ 589	$ (686)	$ (41)
Amortization of unrecognized actuarial gain (loss)	686	814	21
Pension Plan
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss) at beginning of fiscal year	(2,866)	(3,091)
Net gain (loss) arising during period	1,107	(664)
Amortization of unrecognized actuarial gain (loss)	843	977
Tax (expense) benefit of changes during the year, net	(448)	(88)
Accumulated other comprehensive income (loss) at end of fiscal year	(1,364)	(2,866)	(3,091)
SERP
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss) at beginning of fiscal year	484	624
Net gain (loss) arising during period	(517)	(22)
Prior service cost	0	0
Amortization of unrecognized actuarial gain (loss)	(157)	(163)
Amortization of prior service cost and transition obligation	0	0
Tax (expense) benefit of changes during the year, net	155	45
Accumulated other comprehensive income (loss) at end of fiscal year	$ (35)	$ 484	$ 624