Restatement - Statement of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 04, 2015	Jun. 28, 2014	Jul. 04, 2015	Jun. 28, 2014
Cash Flows from Operating Activities
Net Income (Loss)	$ 1,782	$ 6,619	$ (191)	$ 11,778
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Depreciation and amortization	6,514	7,699	13,428	15,125
Stock-based compensation expense			2,461	1,288
Deferred income taxes			1,577	998
Excess tax benefits from stock-based compensation			(509)	(61)
Recovery of doubtful accounts			(28)	(235)
Other			(1,663)	31
Changes in Assets and Liabilities:
Accounts receivable			(106)	(13,066)
Inventories			4,828	(1,694)
Production cost of contracts			1,348	(1,734)
Other assets			7,942	6,563
Accounts payable			(4,078)	(4,363)
Accrued and other liabilities			(10,295)	835
Net Cash Provided by Operating Activities			17,556	15,465
Cash Flows from Financing Activities
Purchases of property and equipment			(7,782)	(5,997)
Proceeds from sale of assets			279	51
Net Cash Used in Investing Activities			(5,993)	(5,946)
Cash Flows from Investing Activities
Repayment of term loan and other debt			(90,013)	(15,012)
Excess tax benefits from stock-based compensation			509	61
Net proceeds from issuance of common stock under stock plans			(1,106)	369
Net Cash Used in Financing Activities			(30,348)	(14,582)
Net Decrease in Cash and Cash Equivalents			(18,785)	(5,063)
Cash and Cash Equivalents at Beginning of Period			45,627	48,814
Cash and Cash Equivalents at End of Period	$ 26,842	43,751	26,842	43,751
Supplemental Disclosures of Cash Flow Information
Interest paid			12,400	1,440
Taxes paid			150	3,249
Non-cash activities:
Purchases of property and equipment not paid			$ 1,871	722
As Reported
Cash Flows from Operating Activities
Net Income (Loss)		6,472		11,101
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Depreciation and amortization				15,125
Stock-based compensation expense				1,288
Deferred income taxes				595
Excess tax benefits from stock-based compensation				(61)
Recovery of doubtful accounts				(235)
Other				1,111
Changes in Assets and Liabilities:
Accounts receivable				(13,066)
Inventories				(1,694)
Production cost of contracts				(1,734)
Other assets				6,563
Accounts payable				(4,363)
Accrued and other liabilities				835
Net Cash Provided by Operating Activities				15,465
Cash Flows from Financing Activities
Purchases of property and equipment				(5,997)
Proceeds from sale of assets				51
Net Cash Used in Investing Activities				(5,946)
Cash Flows from Investing Activities
Repayment of term loan and other debt				(15,012)
Excess tax benefits from stock-based compensation				61
Net proceeds from issuance of common stock under stock plans				369
Net Cash Used in Financing Activities				(14,582)
Net Decrease in Cash and Cash Equivalents				(5,063)
Cash and Cash Equivalents at Beginning of Period				48,814
Cash and Cash Equivalents at End of Period		43,751		43,751
Adjustments
Cash Flows from Operating Activities
Net Income (Loss)		147		677
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Depreciation and amortization				0
Stock-based compensation expense				0
Deferred income taxes				403
Excess tax benefits from stock-based compensation				0
Recovery of doubtful accounts				0
Other				(1,080)
Changes in Assets and Liabilities:
Accounts receivable				0
Inventories				0
Production cost of contracts				0
Other assets				0
Accounts payable				0
Accrued and other liabilities				0
Net Cash Provided by Operating Activities				0
Cash Flows from Financing Activities
Purchases of property and equipment				0
Proceeds from sale of assets				0
Net Cash Used in Investing Activities				0
Cash Flows from Investing Activities
Repayment of term loan and other debt				0
Excess tax benefits from stock-based compensation				0
Net proceeds from issuance of common stock under stock plans				0
Net Cash Used in Financing Activities				0
Net Decrease in Cash and Cash Equivalents				0
Cash and Cash Equivalents at Beginning of Period				0
Cash and Cash Equivalents at End of Period		$ 0		$ 0