XML 64 R52.htm IDEA: XBRL DOCUMENT v3.10.0.1
Senior Debt - Additional Information (Detail) - USD ($)
6 Months Ended
Oct. 31, 2017
Jun. 30, 2018
Jun. 30, 2017
Sep. 30, 2019
Mar. 31, 2019
Dec. 31, 2017
Line Of Credit Facility [Line Items]            
Prepayment of outstanding debt   $ 29,200,000        
Scheduled payments of debt   1,600,000        
Repayments of debt   30,756,000 $ 7,656,000      
Final scheduled principal payment due in September 2020   $ 83,100,000        
Weighted average stated interest rate on outstanding borrowings   4.89%       4.08%
Interest rate swap, fair value, asset   $ 700,000       $ 300,000
Credit facility, date of amendment Oct. 31, 2017          
Maximum consolidated leverage ratio 375.00%          
ING Bank N.V. ("Aarding") [Member]            
Line Of Credit Facility [Line Items]            
Total borrowing capacity   15,200,000        
ING Bank N.V. ("Aarding") [Member] | Bank Overdrafts [Member]            
Line Of Credit Facility [Line Items]            
Aggregate principal amount outstanding under the credit facilities   0       2,800,000
Scenario Forecast [Member]            
Line Of Credit Facility [Line Items]            
Maximum consolidated leverage ratio       325.00% 350.00%  
Credit Agreement [Member]            
Line Of Credit Facility [Line Items]            
Unused credit availability under credit facility   58,200,000       54,600,000
Letters of Credit [Member]            
Line Of Credit Facility [Line Items]            
Aggregate principal amount outstanding under the credit facilities   21,800,000       24,400,000
Bank Guarantee Facility [Member] | ING Bank N.V. ("Aarding") [Member]            
Line Of Credit Facility [Line Items]            
Aggregate principal amount outstanding under the credit facilities   $ 8,700,000       $ 3,900,000