Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt - Additional Information (Detail)

v3.7.0.1
Long-Term Debt - Additional Information (Detail) - USD ($)
6 Months Ended
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Debt Disclosure [Line Items]      
Line of Credit Facility, Maximum Borrowing Capacity   $ 128,000,000  
Debt Issuance Costs, Line of Credit Arrangements, Gross $ 1,100,000    
Write off of Deferred Debt Issuance Cost 600,000    
Long-term Line of Credit $ 37,000,000   $ 25,000,000
Interest Coverage Ratio, Maximum 3.00    
Current Ratio 1.00    
Revolving Credit Facility      
Debt Disclosure [Line Items]      
Line of Credit Facility, Maximum Borrowing Capacity $ 200,000,000    
Interest Rate at Period End 4.3289%    
Revolving Credit Facility | Future Period [Member]      
Debt Disclosure [Line Items]      
Debt To E B I T D Ratio Maximum 4.00    
Revolving Credit Facility | Future Period Two [Member]      
Debt Disclosure [Line Items]      
Debt To E B I T D Ratio Maximum 3.75    
Revolving Credit Facility | Future Period Three [Member]      
Debt Disclosure [Line Items]      
Debt To E B I T D Ratio Maximum 3.50    
Letter of Credit      
Debt Disclosure [Line Items]      
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage 0.50%    
Line of Credit [Member]      
Debt Disclosure [Line Items]      
Letters of Credit Outstanding, Amount $ 800,000   $ 800,000
Line of Credit [Member] | Letter of Credit      
Debt Disclosure [Line Items]      
Line of Credit Facility, Maximum Borrowing Capacity $ 5,000,000.0    
Minimum [Member] | Revolving Credit Facility      
Debt Disclosure [Line Items]      
Interest rate option one, applicable margin rate over Adjusted LIBOR 2.00%    
Interest rate option two, applicable margin rate 3.00%    
Maximum [Member] | Revolving Credit Facility      
Debt Disclosure [Line Items]      
Interest rate option one, applicable margin rate over Adjusted LIBOR 3.00%    
Interest rate option two, applicable margin rate 4.00%    
Interest Payable One [Member] | Revolving Credit Facility      
Debt Disclosure [Line Items]      
Debt Instrument, Interest Payable Period 1 month    
Interest Payable Two [Member] | Revolving Credit Facility      
Debt Disclosure [Line Items]      
Debt Instrument, Interest Payable Period 3 months    
Interest Payable Three [Member] | Revolving Credit Facility      
Debt Disclosure [Line Items]      
Debt Instrument, Interest Payable Period 6 months