Quarterly report pursuant to Section 13 or 15(d)

Financings - Additional Information (Detail)

v3.8.0.1
Financings - Additional Information (Detail) - USD ($)
1 Months Ended 3 Months Ended 9 Months Ended
Jan. 26, 2017
Feb. 28, 2017
Jul. 31, 2016
Aug. 31, 2015
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
May 31, 2016
Financing Activities and Borrowing Arrangements [Line Items]                    
Line of credit facility, maximum borrowing amount $ 50,000,000                  
Line of credit facility, maturity date Jan. 26, 2020                  
Guaranteed borrowing capacity         $ 10,000,000   $ 10,000,000      
Revolving credit facility         40,659,000   40,659,000   $ 25,993,000  
Interest Expenses         400,000 $ 200,000 1,300,000 $ 700,000    
Amortization expense of deferred debt issuance costs         100,000   300,000 200,000    
Notes payable         4,200,000   4,200,000   14,400,000  
Notes payable, current         2,360,000   2,360,000   2,360,000  
Other Noncurrent Assets                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Deferred debt issuance costs         600,000   600,000   200,000  
Maximum                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Amortization expense of deferred debt issuance costs           100,000        
London Interbank Offered Rate (LIBOR)                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Debt instrument, basis spread on variable rate 2.75%                  
Base Rate                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Debt instrument, basis spread on variable rate 1.75%                  
Value Lighting                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Debt refinance amount             3,700,000      
Value Lighting | Debt Instrument Due in Twenty Eighteen November Twenty Two                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Lump sum payment         1,400,000   $ 1,400,000      
Debt instrument maturity date             Nov. 22, 2018      
TNT                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Debt instrument maturity date   Nov. 06, 2017                
Notes payable                   $ 2,000,000
Debt instrument, interest rate                   5.00%
Accrued interest         100,000   $ 100,000      
TNT | Maximum                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Accrued interest                 $ 100,000  
Interest Expenses         100,000 $ 100,000 $ 100,000 100,000    
TNT | Debt Instrument Due in Twenty Seventeen April Twenty First                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Debt instrument maturity date             Apr. 21, 2017      
Notes payable                   $ 1,000,000
TNT | Debt Instrument Due in Twenty Seventeen November Six                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Debt instrument maturity date             Nov. 06, 2017      
Notes payable                   $ 1,000,000
Energy Source                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Interest Expenses               $ 400,000    
Repayment of notes $ 400,000                  
Energy Source | Maximum                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Interest Expenses         $ 200,000   $ 100,000      
Energy Source | Promissory notes                    
Financing Activities and Borrowing Arrangements [Line Items]                    
Debt instrument maturity date     Jan. 20, 2017 Jul. 20, 2016            
Debt instrument, interest rate     7.00% 5.00%            
Notes payable, current       $ 10,000,000