Property, Plant and Equipment - Schedule (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 194,917	$ 169,019
Less accumulated depreciation and amortization	(140,032)	(127,164)
Property, plant and equipment, net	54,885	41,855
Buildings and land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	45,772	43,765
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	65,989	58,715
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	54,896	43,185
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	5,704	5,310
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	17,128	13,617
Capital projects in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 5,428	$ 4,427