Employee benefit plans and deferred compensation (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
Sep. 30, 2013 |
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| Deferred compensation plan | |||
| Employer contribution to 401(k) plans | $ 4.7 | $ 4.3 | $ 3.8 |
| Percentage of liabilities that can be met plan assets | 90.00% | ||
| Investments in mutual funds within the rabbi trust | $ 8.7 | ||
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- References No definition available.
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- Definition Plan assets of a defined benefit plan, as a percentage of projected benefit obligation. No definition available.
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- Definition The amount of the cost recognized during the period for defined contribution plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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