Equity Method Investments ULVAC Cryogenics, Inc. (Detail) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 25,295		$ 27,273
Equity in earnings of equity method investments	$ 1,942	$ 159
ULVAC Cryogenics, Inc.
Schedule of Equity Method Investments [Line Items]
Joint venture interest, percentage	50.00%
Equity method investments	$ 25,300		25,600
Equity in earnings of equity method investments	2,400	400
Management fee payments received	300	200
Charges incurred from related parties		$ 100
Accounts payable for unpaid products and services	$ 100		$ 100