Strategic Alliance and Investment by Elutions, Inc. (Details Textual) - USD ($)			3 Months Ended			6 Months Ended
	Mar. 18, 2014	Feb. 25, 2014	Jul. 02, 2016	Jul. 04, 2015	Oct. 04, 2014	Jul. 02, 2016	Jul. 04, 2015	Jan. 02, 2016
Investment [Line Items]
Outstanding shares percentage (percent)			6.50%			6.50%
Open market outstanding shares percentage (percent)			38.50%			38.50%
Price per share of stock on tracking warrant (in dollars per share)			$ 5.50			$ 5.50
Market development agreement, inventory required to be sold within one year of agreement to avoid discount (percent)		75.00%
Market development agreement, inventory discount against original purchase price, percent		10.00%
Monthly labor expense			$ 36,750
Labor and related expense			0	$ 110,000		$ 98,500	$ 220,500
Estimated remaining license payments			1,100,000
Advance to Elutions			$ 400,000			$ 400,000
Interest rate on advance to Elutions (percent)			5.50%			5.50%
Carrying value of the note			$ 3,269,000			$ 3,269,000		$ 3,269,000
Non-Convertible Promissory Note [Member]
Investment [Line Items]
Fair value of the note			$ 2,793,000			$ 2,793,000		3,004,000
Incentive Warrant [Member]
Investment [Line Items]
Warrants issued to purchase common stock (shares)			3,400,000
Shares vested under the Incentive Warrant (shares)			14,848	5,508		18,934	30,293
Expense recognized on Incentive Warrant			$ 27,000	$ 9,000		$ 34,000	$ 47,000
Incentive Warrant [Member] | Non-Convertible Promissory Note [Member]
Investment [Line Items]
Debt instrument, maturity date			Mar. 18, 2019
Warrant vesting period			5 years
Elutions, Inc [Member]
Investment [Line Items]
Original principal amount of promissory note			$ 3,268,664			3,268,664
Advance to Elutions			300,000			300,000		300,000
Elutions, Inc [Member] | Inventories [Member]
Investment [Line Items]
Inventory purchase obligation			$ 3,000,000.0			$ 3,000,000.0
Payment to acquire inventory					$ 3,000,000.0
Elutions, Inc [Member] | Non-Convertible Promissory Note [Member]
Investment [Line Items]
Stated interest rate (percent)			7.825%			7.825%
Debt instrument, maturity date			Mar. 18, 2019
Debt instrument default interest rate (percent)						9.825%
Interest expense, debt			$ 65,000	$ 63,000		$ 129,000	$ 126,000
Carrying value of the note			3,269,000			3,269,000		$ 3,269,000
Elutions, Inc [Member] | Non-Convertible Promissory Note [Member] | Strategic Alliance and Investment [Member]
Investment [Line Items]
Original principal amount of promissory note			$ 3,268,664			$ 3,268,664
Period after which note may be prepaid if minimum stock price met						18 months
Price per share of stock on tracking warrant (in dollars per share)						$ 5.50
Period after which note may be prepaid						30 months
Revenue, cash recognized and cash collected, percentage used in calculating exercisable warrants (percent)						4.00%
Elutions, Inc [Member] | Common Stock [Member]
Investment [Line Items]
Shares issued and sold (shares)	609,756
Shares sold, price per share (in dollars per share)			$ 3.28			$ 3.28
Proceeds from shares sold	$ 2,000,000
Elutions, Inc [Member] | Tracking Warrant [Member]
Investment [Line Items]
Warrants issued to purchase common stock (shares)						996,544
Warrant exercise price (in dollars per share)	$ 3.28					$ 3.28
Price per share of stock on tracking warrant (in dollars per share)						$ 5.50
Period after which Company may require Elutions to exercise or forfeit warrant if working capital thresholds are met						30 months
Period after which Company may require Elutions to exercise or forfeit warrant if thresholds are met						18 months
Elutions, Inc [Member] | Tracking Warrant [Member] | Strategic Alliance and Investment [Member]
Investment [Line Items]
Warrants issued to purchase common stock (shares)			996,544
Elutions, Inc [Member] | Incentive Warrant [Member]
Investment [Line Items]
Warrants issued to purchase common stock (shares)						3,400,000
Expiration date of warrants issued in period						Mar. 18, 2020
Warrants issued during period exercise price increases per year (in dollars per share)			$ 0.25
Elutions, Inc [Member] | Incentive Warrant [Member] | Minimum [Member]
Investment [Line Items]
Warrant exercise price for warrants issued to Elutions (in dollars per share)			3.85			$ 3.85		$ 3.85
Elutions, Inc [Member] | Incentive Warrant [Member] | Maximum [Member]
Investment [Line Items]
Warrant exercise price for warrants issued to Elutions (in dollars per share)			$ 4.85			$ 4.85		$ 4.85
Other Current Assets [Member] | Elutions, Inc [Member]
Investment [Line Items]
Advance to Elutions			$ 100,000			$ 100,000		$ 100,000
Other Noncurrent Assets [Member] | Elutions, Inc [Member]
Investment [Line Items]
Advance to Elutions			$ 200,000			$ 200,000		$ 200,000
Elutions, Inc [Member]
Investment [Line Items]
Commercial relationship, term of agreement		5 years
Commercial relationship, renewal period		2 years
Commercial relationship, period restrictions apply, after initial term		2 years