Quarterly report pursuant to Section 13 or 15(d)

Restructuring Charges - Additional Information (Details)

v3.7.0.1
Restructuring Charges - Additional Information (Details)
$ in Thousands
 3 Months Ended 6 Months Ended
Dec. 19, 2016
Employee
Mar. 31, 2017
USD ($)
Mar. 31, 2016
USD ($)
Jun. 30, 2017
USD ($)
Employee
Mar. 31, 2018
USD ($)
Dec. 31, 2016
USD ($)
 [1]
Restructuring Cost And Reserve [Line Items]            
Restructuring charges   $ 2,020 $ 36      
Accrued restructuring expenses   1,793       $ 3,594
2016 Restructuring [Member]            
Restructuring Cost And Reserve [Line Items]            
Number of employees terminated | Employee 57          
2016 Restructuring [Member] | Severance, Other Termination Benefits and Outplacement Services [Member]            
Restructuring Cost And Reserve [Line Items]            
Restructuring charges   1,500        
2017 Restructuring [Member] | Severance, Other Termination Benefits and Outplacement Services [Member]            
Restructuring Cost And Reserve [Line Items]            
Restructuring charges   500        
2017 Restructuring [Member] | Forecast [Member]            
Restructuring Cost And Reserve [Line Items]            
Number of additional employees expects to eliminate | Employee       5    
2017 and 2016 Restructuring [Member]            
Restructuring Cost And Reserve [Line Items]            
Payments for restructuring expenses   3,800        
Accrued restructuring expenses   $ 1,800        
2017 and 2016 Restructuring [Member] | Forecast [Member]            
Restructuring Cost And Reserve [Line Items]            
Expected remaining future payments for restructuring       $ 1,000    
2017 and 2016 Restructuring [Member] | Forecast [Member] | Executive Severance [Member]            
Restructuring Cost And Reserve [Line Items]            
Expected remaining future payments for restructuring         $ 800  
[1] The condensed consolidated balance sheet as of December 31, 2016 has been derived from the audited consolidated financial statements as of that date included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016.