Quarterly report pursuant to Section 13 or 15(d)

Supplemental disclosures (Details)

v3.5.0.2
Supplemental disclosures (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Sep. 30, 2015
Aug. 31, 2015
Sep. 30, 2014
Income Taxes Paid, Net [Abstract]              
Income taxes paid     $ 79,500 $ 47,800      
Cash and Cash Equivalents [Abstract]              
Cash and cash equivalents $ 50,609 $ 81,877 50,609 81,877 $ 74,672   $ 158,112
Foreign currency translation adjustments (9,354) $ 8,339 (11,979) (12,694)      
Effect of exchange rate changes on cash and cash equivalents     3,218 4,559      
Decline in goodwill value     6,167        
Payments for Repurchase of Equity [Abstract]              
Stock repurchase programs, authorized amount           $ 200,000  
Repurchases of common stock     (31,336) $ (30,618)      
Amount remaining available for future stock repurchases 137,500   $ 137,500        
Restricted Stock Units (RSUs)              
Employee Benefits and Share-based Compensation [Abstract]              
Granted (in shares)     500,000        
Vesting period     5 years        
Common Stock              
Payments for Repurchase of Equity [Abstract]              
Common shares repurchased     587,000 753,000      
Repurchases of common stock     $ (31,336) $ (30,618)      
Non-U.S.              
Cash and Cash Equivalents [Abstract]              
Cash and cash equivalents 46,900   46,900        
Mutual Fund              
Compensation and Retirement Disclosure [Abstract]              
Investments in mutual funds $ 10,900   $ 10,900