Pension and Retirement Plans - Summary of Various Categories of Pension Plan Assets (Details) - Pension Plan - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$ 50,131	$ 42,648	$ 45,247
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	42,934	36,114
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	7,197	6,534
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	4,834	3,520
Cash and Cash Equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	4,834	3,520
Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	7,197	6,534
Fixed Income | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	7,197	6,534
Common Stock, Large Cap Core
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	17,180	16,127
Common Stock, Large Cap Core | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	17,180	16,127
Common Stock, Small Cap Core
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	2,627	2,090
Common Stock, Small Cap Core | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	2,627	2,090
Mutual Funds, Domestic Equity
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	3,931	4,320
Mutual Funds, Domestic Equity | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	3,931	4,320
Mutual Funds, International
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	3,650	3,409
Mutual Funds, International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	3,650	3,409
Mutual Funds, Domestic Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	10,712	6,648
Mutual Funds, Domestic Fixed Income | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$ 10,712	$ 6,648