Activity of Goodwill by Reportable Operating Segment (Detail) (USD $)	6 Months Ended
	Mar. 28, 2014
Goodwill [Line Items]
Balance, beginning	$ 225,335,000	[1]
Acquisition of business	600,000
Foreign currency translation adjustments	900,000
Balance, ending	226,829,000
Oncology Systems
Goodwill [Line Items]
Balance, beginning	132,000,000
Acquisition of business	600,000
Foreign currency translation adjustments	0
Balance, ending	132,600,000
Imaging Components
Goodwill [Line Items]
Balance, beginning	33,200,000
Acquisition of business	0
Foreign currency translation adjustments	0
Balance, ending	33,200,000
Other
Goodwill [Line Items]
Balance, beginning	60,100,000
Acquisition of business	0
Foreign currency translation adjustments	900,000
Balance, ending	$ 61,000,000

[1] The condensed consolidated balance sheet as of September 27, 2013 was derived from audited financial statements as of that date, but does not include all disclosures required by accounting principles generally accepted in the United States of America.