Quarterly report pursuant to Section 13 or 15(d)

Assets Held for Sale - Additional Information (Details)

v3.20.1
Assets Held for Sale - Additional Information (Details)
3 Months Ended
Mar. 31, 2020
USD ($)
crane
Deckbarge
Mar. 31, 2019
USD ($)
Long Lived Assets Held-for-sale [Line Items]    
Gain (loss) on sale of assets $ 5,000 $ (101,000)
Held for sale    
Long Lived Assets Held-for-sale [Line Items]    
Number of cranes | crane 3  
Number of deck barges | Deckbarge 1  
Proceeds from sale of bending roll machines $ 1,100,000 400,000
Gain (loss) on sale of assets $ 0 400,000
Impairment of long-lived assets to be disposed of   $ 300,000