Goodwill (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Goodwill
Balance at the beginning of the period	$ 185,771	$ 40,549
New acquisitions	27,009	144,378
Translation adjustments	(1,069)	844
Balance at the end of the period	$ 211,711	$ 185,771

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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