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Business Combinations - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Jan. 12, 2015	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2015
Business Acquisition [Line Items]
Goodwill		$ 779,928	$ 773,931	$ 814,750
TONBELLER
Business Acquisition [Line Items]
Common stock acquired	100.00%
Weighted average useful life	4 years 11 months
Goodwill	$ 46,149
Cash consideration	$ 59,632
InfoCentricity
Business Acquisition [Line Items]
Common stock acquired		100.00%
Cash consideration		$ 8,200
Cr Software LLC
Business Acquisition [Line Items]
Common stock acquired			100.00%
Weighted average useful life			8 years 9 months 17 days
Goodwill			$ 13,700
Cash consideration			29,600
Intangible assets acquired			$ 16,500
Infoglide Software Inc
Business Acquisition [Line Items]
Common stock acquired			100.00%
Cash consideration			$ 4,400
Completed technology \| TONBELLER
Business Acquisition [Line Items]
Weighted average useful life	5 years
Customer relationships \| TONBELLER
Business Acquisition [Line Items]
Weighted average useful life	5 years
Trade names \| TONBELLER
Business Acquisition [Line Items]
Weighted average useful life	3 years