Retirement Plans - Summary of Categories in Fair Value Hierarchy (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	$ 50,803	$ 287,270
Not Leveled
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount		227,092
Quoted Prices in Active Markets (Level 1)
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	50,803	53,386
Significant Other Observable Inputs (Level 2)
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	0	0
Significant Unobservable Inputs (Level 3)
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount		6,792
Equity Securities - U.S. Holdings
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	8	7
Equity Securities - U.S. Holdings | Quoted Prices in Active Markets (Level 1)
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	8	7
Bond Funds - Other
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	31,380	173,853
Bond Funds - Other | Not Leveled
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount		173,853
Bond Funds - Other | Quoted Prices in Active Markets (Level 1)
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	31,380
Cash and Cash Equivalents
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	19,415	53,379
Cash and Cash Equivalents | Quoted Prices in Active Markets (Level 1)
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	19,415	53,379
Bond Funds - Government
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	0	53,239
Bond Funds - Government | Not Leveled
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount		53,239
Partnership
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount	$ 0	6,792
Partnership | Significant Unobservable Inputs (Level 3)
Fair values of pension plan assets
Defined Benefit Plan, Plan Assets, Amount		$ 6,792	$ 7,539