Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Financial Instruments - Summary of Changes in Fair Value of Company's Earn-Out Liability (Details)

v3.19.1
Fair Value of Financial Instruments - Summary of Changes in Fair Value of Company's Earn-Out Liability (Details) - USD ($)
 3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Earn-out payments during the period $ 190,473 $ 680,941
Level 3 Inputs    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Balance at December 31, 2018 7,609,384  
Fair value of the earn-out liability associated with the American Stainless acquisition 6,148,230  
Earn-out payments during the period (560,762)  
Changes in fair value during the period 16,523  
Balance at March 31, 2019 13,213,375  
MUSA-Stainless | Level 3 Inputs    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Balance at December 31, 2018 4,251,584  
Fair value of the earn-out liability associated with the American Stainless acquisition 0 $ 154,060
Earn-out payments during the period (370,289)  
Changes in fair value during the period 343,710  
Balance at March 31, 2019 4,225,005  
MUSA-Galvanized | Level 3 Inputs    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Balance at December 31, 2018 3,357,800  
Fair value of the earn-out liability associated with the American Stainless acquisition 0  
Earn-out payments during the period (190,473)  
Changes in fair value during the period (392,958)  
Balance at March 31, 2019 2,774,369  
ASTI | Level 3 Inputs    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Balance at December 31, 2018 0  
Fair value of the earn-out liability associated with the American Stainless acquisition 6,148,230  
Earn-out payments during the period 0  
Changes in fair value during the period 65,771  
Balance at March 31, 2019 $ 6,214,001