Quarterly report pursuant to Section 13 or 15(d)

Line of Credit, Short-Term and Long-Term Borrowings - Long-Term Borrowings (Parenthetical) (Detail)

v3.5.0.2
Line of Credit, Short-Term and Long-Term Borrowings - Long-Term Borrowings (Parenthetical) (Detail)
 6 Months Ended
Jun. 30, 2016
USD ($)
Equipment Notes [Member] | Second Note [Member]  
Debt Instrument [Line Items]  
Monthly repayment installment of note payable $ 483,900
Fixed interest rate of note payable 3.19%
Balloon payment required under note payable, paid $ 11,670,000
Due date for note payable 2016-06
Frequency of periodic payment Monthly
Equipment Notes [Member] | Notes payable to TCF Finance [Member]  
Debt Instrument [Line Items]  
Monthly repayment installment of note payable $ 30,500
Fixed interest rate of note payable 5.24%
Due date for note payable 2019-07
Frequency of periodic payment Monthly
Joint Venture with HF Logistics [Member] | Construction Loan Agreement [Member] | Modification Loan [Member]  
Debt Instrument [Line Items]  
Monthly repayment installment of note payable $ 121,300
Variable interest rate of note payable 2.46%
Balloon payment required under note payable $ 63,692,000
Due date for note payable 2020-08
Frequency of periodic payment Monthly