Quarterly report pursuant to Section 13 or 15(d)

Financing Arrangements - Narrative (Details)

v3.10.0.1
Financing Arrangements - Narrative (Details)
1 Months Ended 3 Months Ended 9 Months Ended 10 Months Ended 12 Months Ended
Mar. 27, 2018
USD ($)
$ / shares
shares
Jan. 06, 2017
USD ($)
Feb. 28, 2015
USD ($)
d
$ / shares
Sep. 30, 2018
USD ($)
$ / shares
Mar. 31, 2018
Sep. 30, 2017
USD ($)
Mar. 31, 2017
USD ($)
Sep. 30, 2018
USD ($)
$ / shares
Sep. 30, 2017
USD ($)
Jan. 25, 2018
USD ($)
Dec. 31, 2017
USD ($)
$ / shares
Jun. 30, 2020
Mar. 08, 2018
$ / shares
shares
Debt Instrument [Line Items]                          
Loss on extinguishment of debt       $ 0   $ 0   $ 0 $ 14,389,000        
Debt instrument, face amount       $ 754,544,000       $ 754,544,000     $ 660,200,000    
Stated interest rate     2.75%                    
Common stock, par value (usd per share) | $ / shares       $ 0.0001       $ 0.0001     $ 0.0001    
Capital lease obligations       $ 1,224,000       $ 1,224,000          
Second Lien Credit Agreement                          
Debt Instrument [Line Items]                          
Debt instrument, face amount       158,450,000       158,450,000     $ 0    
Proceeds from issuance of debt $ 143,000,000                        
Line of Credit                          
Debt Instrument [Line Items]                          
Borrowings outstanding under facility letters                     700,000    
Line of Credit                          
Debt Instrument [Line Items]                          
Maximum borrowing capacity   $ 585,000,000                      
Letters of credit outstanding       $ 6,500,000       $ 6,500,000          
Percentage of outstanding equity in foreign subsidiaries pledged as collateral       65.00%       65.00%          
Ratio of Indebtedness to Net Capital   4.5                      
Line of Credit | Secured Debt                          
Debt Instrument [Line Items]                          
Maximum borrowing capacity   $ 500,000,000                      
Periodic payment, period one   0.25%   0.625%       0.625%          
Line of Credit | Revolving Credit Facility                          
Debt Instrument [Line Items]                          
Maximum borrowing capacity   $ 85,000,000                      
Loss on extinguishment of debt             $ (14,500,000)            
Line of Credit | Letters of Credit                          
Debt Instrument [Line Items]                          
Maximum borrowing capacity   $ 15,000,000                      
Letters of credit outstanding       $ 5,800,000       $ 5,800,000          
Convertible senior notes                          
Debt Instrument [Line Items]                          
Debt instrument, face amount       $ 82,500,000       $ 82,500,000     82,500,000    
Stated interest rate     2.75% 2.75%       2.75%          
Beneficial ownership percentage 9.90%                        
Conversion ratio     0.0539084                    
Conversion price (in usd per share) | $ / shares     $ 18.55                    
Convertible debt     $ 69,500,000 $ 70,200,000       $ 70,200,000     69,700,000    
Equity component of convertible debt     13,000,000 13,000,000       13,000,000          
Increase in stated rate, first ninety days                   0.25%      
Increase in stated rate, second ninety days                   0.50%      
Debt Instrument, Penalty Interest Incurred                   $ 200,000      
Convertible senior notes | Liability component                          
Debt Instrument [Line Items]                          
Debt issuance costs     1,800,000                    
Convertible senior notes | Additional paid-in capital                          
Debt Instrument [Line Items]                          
Debt issuance costs     $ 300,000                    
Convertible senior notes | If company undergoes a fundamental change                          
Debt Instrument [Line Items]                          
Redemption price percentage     100.00%                    
Convertible senior notes | On or after February 20, 2019                          
Debt Instrument [Line Items]                          
Percent of stock price to trigger conversion     130.00%                    
Consecutive trading days | d     30                    
Trading days | d     20                    
Convertible senior notes | On or after February 20, 2022                          
Debt Instrument [Line Items]                          
Redemption price percentage     100.00%                    
Convertible senior notes | Redemption scenario one | After March 31, 2015                          
Debt Instrument [Line Items]                          
Percent of stock price to trigger conversion     130.00%                    
Convertible senior notes | Redemption scenario two | After March 31, 2015                          
Debt Instrument [Line Items]                          
Percent of stock price to trigger conversion     98.00%                    
Consecutive business days | d     5                    
Term loan facility                          
Debt Instrument [Line Items]                          
Debt instrument, face amount       481,250,000       481,250,000     490,625,000    
Commercial Mortgage Loan | Mortgage letters maturing October 2032 | IFES Acquisition Corp Limited                          
Debt Instrument [Line Items]                          
Accrued interest on mortgage letters                     0    
Subordinated Debt                          
Debt Instrument [Line Items]                          
Debt instrument, face amount       $ 158,450,000       $ 158,450,000     $ 0    
Stated interest rate 10.00%                        
Covenant net leverage ratio 3.39                        
Paid-in-kind interest rate 12.00%                        
Proceeds from issuance of debt $ 150,000,000                        
Subordinated Debt | After March 31, 2015                          
Debt Instrument [Line Items]                          
Redemption price percentage 100.00%                        
Subordinated Debt | If company undergoes a fundamental change                          
Debt Instrument [Line Items]                          
Redemption price percentage 100.00%                        
Subordinated Debt | On or after February 20, 2019                          
Debt Instrument [Line Items]                          
Redemption price percentage 105.00%                        
Subordinated Debt | On or after February 20, 2022                          
Debt Instrument [Line Items]                          
Redemption price percentage 102.50%                        
Subordinated Debt | Debt Instrument, Redemption, Period Five [Member]                          
Debt Instrument [Line Items]                          
Redemption price percentage 101.00%                        
Liability Warrants                          
Debt Instrument [Line Items]                          
Beneficial ownership percentage 19.90%                        
Proceeds from issuance of debt $ 150,000,000                        
Adjusted Base Eurocurrency Rate | Line of Credit | Secured Debt                          
Debt Instrument [Line Items]                          
Basis spread on variable rate   6.00%           7.50%          
Adjusted Base Eurocurrency Rate | Line of Credit | Revolving Credit Facility                          
Debt Instrument [Line Items]                          
Basis spread on variable rate   6.00%     7.50%                
Adjusted Base Eurocurrency Rate | Line of Credit | Revolving Credit Facility | Minimum                          
Debt Instrument [Line Items]                          
Basis spread on variable rate   5.50%   7.00%                  
Adjusted Base Eurocurrency Rate | Line of Credit | Revolving Credit Facility | Maximum                          
Debt Instrument [Line Items]                          
Basis spread on variable rate   6.00%   7.50%                  
Base Rate | Line of Credit | Secured Debt                          
Debt Instrument [Line Items]                          
Basis spread on variable rate   5.00%           6.50%          
Base Rate | Line of Credit | Revolving Credit Facility                          
Debt Instrument [Line Items]                          
Basis spread on variable rate   5.00%     6.50%                
Base Rate | Line of Credit | Revolving Credit Facility | Minimum                          
Debt Instrument [Line Items]                          
Basis spread on variable rate   4.50%   6.00%                  
Base Rate | Line of Credit | Revolving Credit Facility | Maximum                          
Debt Instrument [Line Items]                          
Basis spread on variable rate   5.00%   6.50%                  
Penny Warrants                          
Debt Instrument [Line Items]                          
Exercise price (in usd per share) | $ / shares       $ 0.01       $ 0.01          
Penny Warrants | Liability Warrants                          
Debt Instrument [Line Items]                          
Number of securities called by warrants | shares 18,065,775                       18,065,775
Common stock, par value (usd per share) | $ / shares $ 0.0001                        
Exercise price (in usd per share) | $ / shares 0.01                       $ 0.01
Stock price trigger | $ / shares $ 4.00                        
Penny Warrants | Liability Warrants | Minimum                          
Debt Instrument [Line Items]                          
Beneficial ownership percentage 50.00%                        
Percentage of warrants held to nominate for BOD 25.00%                        
Penny Warrants | Liability Warrants | Maximum                          
Debt Instrument [Line Items]                          
Percentage of warrants held to nominate for BOD 50.00%                        
Market Warrants                          
Debt Instrument [Line Items]                          
Exercise price (in usd per share) | $ / shares       $ 1.57       $ 1.57          
Market Warrants | Liability Warrants                          
Debt Instrument [Line Items]                          
Number of securities called by warrants | shares 13,000,000                       13,000,000
Exercise price (in usd per share) | $ / shares $ 1.57                       $ 1.57
Stock price trigger | $ / shares $ 2.40                        
Market Warrants | Liability Warrants | Minimum                          
Debt Instrument [Line Items]                          
Beneficial ownership percentage 25.00%                        
Forecast [Member] | Line of Credit | Secured Debt                          
Debt Instrument [Line Items]                          
Periodic payment, period one                       1.25%