Business Combinations (Details) - USD ($) $ in Thousands		9 Months Ended
	Jun. 02, 2017	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2016
Fair value of assets acquired
Goodwill		$ 51,967		$ 4,718
MOTIVE Merger
Business Combinations
Payment for business acquisition	$ 74,275
Future potential earnout payments	25,000
Business acquisition transaction cost		2,800
Revenues		1,100
Net loss		(700)
Expected annual amortization		3,400
Purchase Price
Payment for business acquisition	74,275
Long-term contingent earnout liability (Other noncurrent liabilities)	14,509
Total cash consideration given	88,784
Fair value of assets acquired
Current assets	4,425
Property, plant and equipment	300
Goodwill	47,249
Total assets acquired	102,974
Fair value of liabilities assumed
Current liabilities	25
Deferred income taxes	14,165
Total liabilities acquired	14,190
Fair value of total assets and liabilities acquired	$ 88,784
Proforma financial information:
After tax transaction cost adjusted for proforma financial information		1,000
Business Acquisition, Pro Forma Revenue		1,275,646	$ 1,294,146
Net loss		$ (105,482)	$ (18,292)
MOTIVE Merger | Developed technology
Business Combinations
Amortization period of developed technology	15 years
Fair value of assets acquired
Intangible asset - developed technology (Intangible assets, net of amortization)	$ 51,000