Restructuring Charges - Table of Charges Taken Related to Restructuring Actions (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 29, 2012	Sep. 29, 2012
Restructuring Cost and Reserve [Line Items]
Non-cash impairment charge		$ 16,901
Purchase orders and other contractual obligations		3,099
Workforce reductions		15,249
Facility closure costs		430
Other		900
Fiscal charges		36,579
Recorded to cost of product sales		19,064
Recorded to restructuring		17,515
Fiscal charges		36,579
Non-cash impairment charges		(16,901)
Stock compensation	(222)	(3,500)
Severance payments	(6,828)	(2,629)
Purchase orders and other contractual obligations payments	(738)	(2,572)
Other payments		(430)
Acquired		83
Foreign exchange and other adjustments	5	113
Balance at December 29, 2012	6,893	10,743
Fiscal 2013 charges [Member] | Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions		3,281
Other		652
Fiscal charges	3,933	3,933
Fiscal charges	3,933	3,933
Abandonment of Adiana Product Line [Member]
Restructuring Cost and Reserve [Line Items]
Non-cash impairment charge		16,316
Purchase orders and other contractual obligations		3,099
Workforce reductions		128
Fiscal charges		19,543
Recorded to cost of product sales		19,064
Recorded to restructuring		479
Fiscal charges		19,543
Non-cash impairment charges		(16,316)
Severance payments		(128)
Purchase orders and other contractual obligations payments	(527)	(2,572)
Balance at December 29, 2012		527
Consolidation of Diagnostics Operations [Member]
Restructuring Cost and Reserve [Line Items]
Non-cash impairment charge		585
Workforce reductions		14,202
Fiscal charges		14,787
Recorded to restructuring		14,787
Fiscal charges		14,787
Non-cash impairment charges		(585)
Stock compensation	(222)	(3,500)
Severance payments	(6,775)	(2,423)
Acquired		83
Foreign exchange and other adjustments	5	22
Balance at December 29, 2012	3,184	8,384
Consolidation of Diagnostics Operations [Member] | Fiscal 2013 charges [Member] | Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions		1,792
Fiscal charges	1,792	1,792
Fiscal charges	1,792	1,792
Closure of Indianapolis Facility [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions		879
Other		900
Fiscal charges		1,779
Recorded to restructuring		1,779
Fiscal charges		1,779
Purchase orders and other contractual obligations payments	(211)
Balance at December 29, 2012	3,709	1,779
Closure of Indianapolis Facility [Member] | Fiscal 2013 charges [Member] | Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions		1,489
Other		652
Fiscal charges	2,141	2,141
Fiscal charges	2,141	2,141
Other Operating Cost Reductions [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions		40
Facility closure costs		430
Fiscal charges		470
Recorded to restructuring		470
Fiscal charges		470
Severance payments	(53)	(78)
Other payments		(430)
Foreign exchange and other adjustments		91
Balance at December 29, 2012		$ 53