Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 21, 2015	Sep. 25, 2016	Sep. 27, 2015	Sep. 25, 2016	Sep. 27, 2015	Dec. 27, 2015	Jul. 08, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, plant and equipment, net		$ 47.3		$ 47.3		$ 56.2
Fiscal year duration				364 days		364 days
First quarter duration		91 days	91 days	91 days	91 days
Air Force Research Laboratory ('AFRL')
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cost-share contract, award value							$ 40.8
Government funding to be received							7.3
Investment obligation							33.5
Costs expected to be capitalized		$ 14.2		$ 14.2
Total expected costs to be incurred		26.0		26.0
Estimate of loss accrual		$ 16.6		$ 16.6			$ 18.7
Minimum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Fiscal year duration				364 days
Maximum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Fiscal year duration				371 days
Herley
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Estimated cost of disposal	$ 11.5
Ownership percentage (percent)		100.00%		100.00%
Walterboro Facility | Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, plant and equipment, net		$ 1.9		$ 1.9