Note 11 - Stock-based Compensation (Details Textual)		1 Months Ended						3 Months Ended			5 Months Ended	9 Months Ended			12 Months Ended
	Jul. 01, 2016 shares	Jul. 31, 2016 shares	Jan. 31, 2014 shares	Oct. 31, 2013 shares	Mar. 31, 2012 shares	Jan. 31, 2012 shares	Jan. 31, 2012	Jan. 01, 2017 USD ($) $ / shares shares	Jul. 03, 2016 USD ($)	Dec. 27, 2015 USD ($)	Dec. 31, 2014 shares	Jan. 01, 2017 USD ($) $ / shares Rate shares	Dec. 27, 2015 USD ($)	Dec. 28, 2014	Mar. 27, 2016 USD ($) $ / shares shares	Sep. 18, 2014 shares	Jun. 30, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number								5,474,151				5,474,151			7,722,383
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized								4,500,000				4,500,000
Share Price | $ / shares								$ 10.78				$ 10.78			$ 5.26
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross												1,466,800
Allocated Share-based Compensation Expense | $								$ 3,634,000		$ 811,000		$ 7,131,000	$ 3,810,000
Accrued Bonuses, Current | $								1,200,000				$ 1,200,000			$ 1,200,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period												622,039
Chief Executive Officer [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			140,000			480,000
Share-based Compensation Arrangement by Share-based Payment Award, Vesting, Number of Installments							4
Allocated Share-based Compensation Expense, Adjustment | $															(34,000)
Chief Executive Officer [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	280,000
Chief Executive Officer [Member] | Performance-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Vesting, Number of Installments					3
Allocated Share-based Compensation Expense, Adjustment | $															$ (41,000)
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		60,000			300,000
Chief Financial Officer [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	120,000
Allocated Share-based Compensation Expense | $												$ 200,000
Chief Financial Officer [Member] | Performance-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		30,000
Chief Executive Officer and Chief Financial Officer [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Chief Executive Officer and Chief Financial Officer [Member] | Performance-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years
Allocated Share-based Compensation Expense | $								56,000				$ 80,000
Chief Executive Officer and Chief Financial Officer [Member] | Performance-based RSUs [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		1 year
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		33.33%
Chief Executive Officer and Chief Financial Officer [Member] | Performance-based RSUs [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		2 years
Former Cadeka Employees [Member]
Former Employees, Number															5
Payments to Employees | $															$ 75,000
Employees Unsettled, Number												2
Former Cadeka Employees [Member] | Other Current Liabilities [Member]
Accrued Bonuses, Current | $								1,200,000				$ 1,200,000
Former Cadeka Employees [Member] | Restricted Stock Units (RSUs) [Member]
Allocated Share-based Compensation Expense | $													200,000
Certain Executives [Member] | October 2013 PRSUs [Member]
Allocated Share-based Compensation Expense | $								5,000		$ 18,000		42,000	$ 96,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				70,000
Number of Executives Terminated														1
Certain Executives [Member] | October 2013 PRSUs [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Vesting, Number of Installments				3
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				3 years
Certain Executives [Member] | October 2013 PRSUs [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Vesting, Number of Installments				3
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				3 years
Former IML Employees [Member] | Performance-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Vesting, Number of Installments											3
Allocated Share-based Compensation Expense, Adjustment | $									$ (311,000)
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period											3 years
Allocated Share-based Compensation Expense | $								$ 200,000				$ 700,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period											88,448
Employee Stock Participation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent | Rate												95.00%
2006 Plan and Sipex 2006 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number																	6,555,492
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized																	669,008
2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized																5,170,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Per Award												2
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant								3,300,000				3,300,000
The 2017 Incentive Program [Member]
Allocated Share-based Compensation Expense | $												$ 2,200,000