Quarterly report pursuant to Section 13 or 15(d)

Nature of Business and Basis of Presentation - ASC 606 (Details)

v3.10.0.1
Nature of Business and Basis of Presentation - ASC 606 (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Jan. 01, 2018
Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]            
Receivables, net         $ 56,250  
Unbilled receivables, net $ 35,771   $ 35,771   47,069 $ 42,577
Inventories, net 166,486   166,486   130,038 132,591
Accounts payable 48,219   48,219   65,517 66,015
Accrued expenses and other current liabilities 36,282   36,282   40,898 40,243
Deferred tax liabilities 18,337   18,337   20,000 19,423
Retained earnings 292,930   292,930   269,597 267,902
Revenues 168,931 $ 174,164 516,222 $ 565,318    
Provision for income taxes 3,323 3,251 8,611 12,541    
Net income 10,034 6,639 25,837 21,739    
Products            
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]            
Revenues 85,886 82,314 264,678 260,585    
Costs and expenses 72,256 68,678 222,816 217,606    
Services            
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]            
Revenues 83,045 91,850 251,544 304,733    
Costs and expenses 77,810 $ 88,989 239,536 $ 293,083    
Without Adoption of ASC 606            
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]            
Receivables, net           55,760
Unbilled receivables, net 29,341   29,341     42,577
Inventories, net 170,221   170,221     132,591
Accounts payable           66,015
Accrued expenses and other current liabilities 36,282   36,282     40,243
Deferred tax liabilities 17,574   17,574     19,423
Retained earnings 290,998   290,998     $ 267,902
Accounting Standards Update 2014-09 | Effect of ASC 606 Increase/(Decrease)            
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]            
Receivables, net         490  
Unbilled receivables, net         4,492  
Inventories, net         (2,553)  
Accounts payable         (498)  
Accrued expenses and other current liabilities         655  
Deferred tax liabilities         577  
Retained earnings         $ 1,695  
Provision for income taxes 3,345   8,425      
Net income 10,099   25,290      
Accounting Standards Update 2014-09 | Effect of ASC 606 Increase/(Decrease) | Products            
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]            
Revenues 85,625   263,094      
Costs and expenses 72,089   221,634      
Accounting Standards Update 2014-09 | Effect of ASC 606 Increase/(Decrease) | Services            
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]            
Revenues 83,227   251,213      
Costs and expenses $ 77,810   $ 239,536