Annual report pursuant to Section 13 and 15(d)

Savings, Multi-Employer And Defined Benefit Pension Plans (Details)

v3.20.4
Savings, Multi-Employer And Defined Benefit Pension Plans (Details) - USD ($)
$ in Thousands
6 Months Ended 12 Months Ended
Dec. 31, 2017
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Sep. 30, 2019
Defined Benefit Plan Disclosure [Line Items]          
Employer matching contribution percent of employees' gross pay   3.50%      
Savings Plan, cost   $ 2,400 $ 2,200 $ 2,000  
Deferred Compensation Plan, maximum annual salary deferral, percentage   75.00%      
Deferred Compensation Plan, maximum cash bonus deferral, percentage   100.00%      
Deferred Compensation Plan obligation   $ 900 800    
ISH Retirement Plan          
Defined Benefit Plan Disclosure [Line Items]          
Pension expense $ 900 $ 2,200 $ 500    
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate   3.10% 4.05% 3.50%  
Defined Benefit Plan, Assumptions used Calculating Net periodic benefit cost, Expected long-term rate of return on plan assets   6.00% 6.75% 6.75%  
Defined Benefit Plan [Abstract]          
Fair Value of Assets   $ 38,259 $ 37,723    
Projected Benefit Obligation   (40,289) (37,583)    
Funded (Unfunded) Status   $ (2,030) $ 140    
Defined Benefit Plan, Assumptions Used in Calculations [Abstract]          
Benefit obligation, Discount rate   2.30% 3.10%    
Benefit obligation, CPI   2.25% 2.25%    
Benefit obligation, Cash balance interest credits (compounded annually)   3.00% 4.00%    
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Expected long-term rate of return on plan assets   0.0400 0.0600    
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]          
2021   $ 2,260      
2022   2,270      
2023   2,250      
2024   2,210      
2025   2,270      
American Maritime Officers Pension Plan | Withdrawal from Multiemployer Defined Benefit Plan          
Defined Benefit Plan Disclosure [Line Items]          
Loss contingency, estimate of possible loss         $ 25,500
Multiemployer Plans, Pension          
Defined Benefit Plan Disclosure [Line Items]          
Multiemployer plan, contributions by employer   2,400 $ 2,600 $ 2,500  
Multiemployer Plans, Postretirement Benefit          
Defined Benefit Plan Disclosure [Line Items]          
Multiemployer plan, contributions by employer   $ 1,000 $ 1,100 $ 1,000