Note 5 - Goodwill and Acquired Intangible Assets - Summary of Acquired Intangible Assets (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Gross Carrying Amount, Total	$ 27,995,000	$ 28,102,000
Net Carrying Amount, Total	26,580,000	27,187,000
Gross Carrying Amount, Indefinite-Lived Intangible Assets	16,170,000	16,170,000
Indefinite-Lived Intangible Assets (Excluding Goodwill)	16,170,000	16,170,000
Accumulated Amortization, Finite-Lived Intangible Assets	1,415,000	915,000
Net Carrying Amount, Finite-Lived Intangible Assets	10,410,000	11,017,000
Other Intangible Assets [Member]
Gross Carrying Amount, Finite-Lived Intangible Assets	682,000	632,000
Accumulated Amortization, Finite-Lived Intangible Assets	564,000	518,000
Net Carrying Amount, Finite-Lived Intangible Assets	$ 118,000	$ 114,000
Other Intangible Assets [Member] | Minimum [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	5 years	5 years
Other Intangible Assets [Member] | Maximum [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	10 years	10 years
Imugen [Member] | Technology-Based Intangible Assets [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	15 years	15 years
Gross Carrying Amount, Finite-Lived Intangible Assets	$ 5,100,000	$ 5,100,000
Accumulated Amortization, Finite-Lived Intangible Assets	340,000	170,000
Net Carrying Amount, Finite-Lived Intangible Assets	$ 4,760,000	$ 4,930,000
Imugen [Member] | Customer Relationships [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	10 years	10 years
Gross Carrying Amount, Finite-Lived Intangible Assets	$ 2,700,000	$ 2,700,000
Accumulated Amortization, Finite-Lived Intangible Assets	270,000	135,000
Net Carrying Amount, Finite-Lived Intangible Assets	$ 2,430,000	$ 2,565,000
Imugen [Member] | Trademarks and Trade Names [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	16 years	16 years
Gross Carrying Amount, Finite-Lived Intangible Assets	$ 1,900,000	$ 1,900,000
Accumulated Amortization, Finite-Lived Intangible Assets	118,000	59,000
Net Carrying Amount, Finite-Lived Intangible Assets	$ 1,782,000	$ 1,841,000
Immunetics [Member] | Technology-Based Intangible Assets [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	15 years	15 years
Gross Carrying Amount, Finite-Lived Intangible Assets	$ 883,000	$ 860,000
Accumulated Amortization, Finite-Lived Intangible Assets	42,000	9,000
Net Carrying Amount, Finite-Lived Intangible Assets	841,000	851,000
Immunetics [Member] | Customer Relationships [Member]
Gross Carrying Amount, Finite-Lived Intangible Assets	350,000	400,000
Accumulated Amortization, Finite-Lived Intangible Assets	40,000	11,000
Net Carrying Amount, Finite-Lived Intangible Assets	$ 310,000	$ 389,000
Immunetics [Member] | Customer Relationships [Member] | Minimum [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	5 years	5 years
Immunetics [Member] | Customer Relationships [Member] | Maximum [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	11 years	11 years
Immunetics [Member] | Trade Names [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	5 years	5 years
Gross Carrying Amount, Finite-Lived Intangible Assets	$ 160,000	$ 290,000
Accumulated Amortization, Finite-Lived Intangible Assets	23,000	9,000
Net Carrying Amount, Finite-Lived Intangible Assets	$ 137,000	$ 281,000
Immunetics [Member] | Grants [Member]
Amortization Period, Finite-Lived Intangible Assets (Year)	2 years	2 years
Gross Carrying Amount, Finite-Lived Intangible Assets	$ 50,000	$ 50,000
Accumulated Amortization, Finite-Lived Intangible Assets	18,000	4,000
Net Carrying Amount, Finite-Lived Intangible Assets	32,000	46,000
In Process Research and Development [Member] | Imugen [Member]
Gross Carrying Amount, Indefinite-Lived Intangible Assets	9,200,000	9,200,000
Indefinite-Lived Intangible Assets (Excluding Goodwill)	9,200,000	9,200,000
In Process Research and Development [Member] | Immunetics [Member]
Gross Carrying Amount, Indefinite-Lived Intangible Assets	6,970,000	6,970,000
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 6,970,000	$ 6,970,000