v2.4.0.8
Income Taxes (Narrative) (Details) (USD $)
 3 Months Ended 12 Months Ended
Sep. 30, 2012
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2012
Sep. 30, 2011
Income Tax Disclosure [Line Items]          
Effective income tax rate   14.00% (14.00%) 129.00%  
Income before income taxes   $ 186,112,000 $ 126,234,000 $ 120,736,000  
Statutory federal income tax rate   35.00% 35.00% 35.00%  
Deferred tax assets, change in valuation allowance 124,500,000        
Effective Income Tax Rate Reconciliation, Foreign Income Tax Withholding, Amount   5,100,000 6,000,000    
Effective Income Tax Rate Reconciliation, Tax Settlement, Foreign, Amount     5,300,000    
Effect of change in the tax status of the foreign legal entity       4,200,000  
Effective income tax rate, one-time increase   0.00% 0.00% 3.00%  
Tax provision related to research and development cost sharing prepayment   2,000,000   7,800,000  
Deferred Tax Liabilities, Net   136,196,000 120,796,000    
Prepaid income taxes   6,300,000 11,500,000    
Income taxes payable   17,700,000 14,400,000    
Accrued income taxes   9,300,000 7,100,000    
Other current liabilities   1,300,000 2,100,000    
Other liabilities   7,100,000 5,200,000    
Income tax payments   25,500,000 35,400,000 53,000,000  
Net deferred tax assets   2,802,000 4,400,000    
Net operating loss carryforwards   97,200,000      
Valuation allowance 170,400,000 177,541,000 156,547,000 170,400,000 38,600,000
Interest expense   300,000 (1,200,000) 300,000  
Penalty expense   0   100,000  
Interest expense related to income tax accruals   1,400,000 1,100,000    
Accrued tax penalties     100,000    
Unrecognized tax benefit 19,100,000 15,000,000 13,700,000 19,100,000 16,200,000
Income tax provision upon recognition of unrecognized tax benefit   13,800,000      
Unrecognized tax benefits, increase in valuation allowance upon recognition   7,600,000      
Unrecognized tax benefits, increase to additional paid-in capital upon recognition   1,200,000      
Potential decrease in unrecognized tax benefits   2,000,000      
Stock-based compensation   50,889,000 48,787,000 51,305,000  
Tax benefit recognition related to stock based compensation   700,000 2,700,000 3,900,000  
Increase (decrease) in income taxes payable   (19,134,000) 15,211,000 4,005,000  
Windfall tax deductions not yet recognized   21,000,000      
Undistributed Earnings of Foreign Subsidiaries   642,000,000 378,000,000    
Deferred Tax Assets, Tax Credit Carryforwards, Foreign   9,022,000 5,994,000    
Domestic Country [Member]
          
Income Tax Disclosure [Line Items]          
Valuation allowance   144,000,000      
Deferred Tax Assets, Tax Credit Carryforwards, Foreign   9,000,000      
Domestic Country [Member] | Research Tax Credit Carryforward [Member]
          
Income Tax Disclosure [Line Items]          
Credit carryforwards   17,700,000      
Foreign Country [Member]
          
Income Tax Disclosure [Line Items]          
Net operating loss carryforwards   187,300,000      
Valuation allowance   33,500,000      
Credit carryforwards   7,400,000      
Japan [Member]
          
Income Tax Disclosure [Line Items]          
Impact of a Japanese legislative change on our Japan entities' deferred tax assets       1,400,000  
Windfall Tax Benefit [Member]
          
Income Tax Disclosure [Line Items]          
Increase (decrease) in income taxes payable   10,400,000 300,000 1,100,000  
Windfall tax deductions not yet recognized   21,000,000      
Massachusetts Research And Development Member | Research Tax Credit Carryforward [Member]
          
Income Tax Disclosure [Line Items]          
Credit carryforwards   21,300,000      
2014 Acquisitions [Member]
          
Income Tax Disclosure [Line Items]          
Deferred Tax Liabilities, Net   21,600,000      
Servigistics, Enigma and NetIDEAS [Member]
          
Income Tax Disclosure [Line Items]          
Deferred Tax Liabilities, Net     38,672,000    
All Acquisitions [Member]
          
Income Tax Disclosure [Line Items]          
Net operating loss carryforwards   82,700,000      
Axeda and ThingWorx [Member]
          
Income Tax Disclosure [Line Items]          
Deferred tax assets, change in valuation allowance   (18,100,000)      
Net operating loss carryforwards   63,500,000      
Servigistics and Enigma [Member]
          
Income Tax Disclosure [Line Items]          
Deferred tax assets, change in valuation allowance     (36,700,000)    
Prior Acquisitions [Member]
          
Income Tax Disclosure [Line Items]          
Net operating loss carryforwards   19,200,000      
Deferred Tax Asset, Pension [Member]
          
Income Tax Disclosure [Line Items]          
Deferred tax assets, change in valuation allowance   $ (7,900,000)