Annual report pursuant to Section 13 and 15(d)

Multiemployer Pension Plans (Details Textual)

v3.19.1
Multiemployer Pension Plans (Details Textual)
$ in Thousands
12 Months Ended
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Multiemployer Plans [Line Items]    
Multiemployer Plans Contribution And Pension Protection Act Zone Status Description MEPPs in which the Company participates. Additionally, this table also lists the PPA Zone Status for MEPPS as the critical status (red zone-less than 65% funded), the endangered status (yellow-less than 80% funded), the seriously endangered status (orange-less than 80% funded and projects a credit balance deficit within seven years) or neither critical or endangered status (green-greater than 80% funded). The zone status represents the most recent available information for the respective MEPP, which is 2017 for the 2018 year. These dates may not correspond with the Company's calendar year contributions.  
Multiemployer Plan, Contributions by Employer $ 16,439 $ 15,024
Multiemployer Plans Surcharge Percentage 70.00%  
Multiemployer Plans, Pension [Member]    
Multiemployer Plans [Line Items]    
Multiemployer Plans Number Of Employer 40  
Multiemployer Plans, Pension [Member] | Pension Protection Act [Member]    
Multiemployer Plans [Line Items]    
Multiemployer Plans Surcharge Percentage 5.00%  
Multiemployer Plans, Pension [Member] | Retirement Benefit Plan [Member]    
Multiemployer Plans [Line Items]    
Multiemployer Plans Surcharge Percentage 10.00%