Restructuring Expenses - Additional Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Jun. 30, 2017 USD ($) Employee	Jun. 30, 2017 USD ($) Employee
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 4,500	$ 4,471
Facilities charges
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1,700	1,729
Employee separation
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 2,800	$ 2,742
Number of positions eliminated | Employee	79	79