Note 7 - Convertible Debentures (Details Textual) - USD ($)							1 Months Ended	3 Months Ended	6 Months Ended		12 Months Ended
	Dec. 01, 2017	Aug. 22, 2016	Aug. 03, 2016	Feb. 29, 2016	Feb. 16, 2016	Aug. 31, 2015	Feb. 29, 2016	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Stock Issued During Period, Shares, New Issues	898,402		600,000
Stock Issued During Period, Value, New Issues									$ 2,368,000		$ 2,092,000	$ 2,464,000
Debt Conversion, Converted Instrument, Shares Issued		6,102,941
Amortization of Debt Discount (Premium)											9,851,000	6,127,000
Amortization of Debt Issuance Costs											$ 160,000	$ 800,000
Class of Warrant or Right, Outstanding									4,828,723		4,828,723	4,828,723	252,620
Approval for Grant in Amount for Clinical Trial						$ 10,000,000
Proceeds from Convertible Debt												$ 18,000,000
Registration Payment Arrangement, Gains and Losses												(1,100,000)
Derivative, Gain (Loss) on Derivative, Net									133,000	(174,000)	(60,000)	3,395,000
Gain (Loss) on Extinguishment of Debt												$ (795,000)
Warrants Issued in Connection with Convertible Debentures [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights				3,529,412			3,529,412
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 8			$ 8
Warrant Expiration Period							5 years
Number of Warrants, Percentage of Shares Issued or to Be Issued							80.00%
Series B Warrant [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights						606,618
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 13.60
Warrant Expiration Period						1 year 180 days
Class of Warrant or Right, Outstanding						222,427
Shares Issued for Cashless Exercise of Warrants					125,000
Class of Warrant or Right, Cancelled During Period,Value					$ 159,000
Series A Warrant [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 8			$ 8
Class of Warrant or Right, Outstanding						404,412						404,412
Fair Value Assumptions, Expected Volatility Rate				91.00%
Fair Value Inputs, Discount Rate				1.20%
Fair Value Assumptions, Expected Term				5 years
Fair Value Assumptions, Expected Dividend Rate				0.00%
Series A Warrant [Member] | Other Expense [Member]
Derivative, Gain (Loss) on Derivative, Net												$ (149,000)
Common Stock [Member]
Stock Issued During Period, Shares, New Issues									898,402		600,000	735,294
Stock Issued During Period, Value, New Issues									$ 1,000		$ 1,000	$ 1,000
Convertible Debt [Member] | Boyalife Investment Inc. [Member]
Debt Conversion, Original Debt Principal, Amount		$ 12,500,000
Debt Conversion, Original Debt Interest, Amount		8,250,000
Additional Interest Expense, Debt		3,153,000
Amortization of Debt Discount (Premium)		9,538,000
Amortization of Debt Issuance Costs		$ 155,000
Convertible Debt [Member] | Boyalife Investment Inc. [Member] | Common Stock [Member]
Debt Conversion, Convertible Shares				3,676,471			3,676,471
Debt Conversion, Converted Instrument, Shares Issued		6,102,941
Convertible Debt [Member] | Boyalife Investment Inc. [Member] | Common Stock [Member] | Conversion of Interest [Member]
Debt Conversion, Converted Instrument, Shares Issued		2,426,470
Debt Conversion, Converted Instrument, Amount		$ 11,403,000
Thirty-Year Debentures [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights						1,102,942
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 13.60
Warrant Expiration Period						5 years 182 days
Amortization of Debt Discount (Premium)					4,648,000							4,720,000
Amortization of Debt Issuance Costs					$ 765,000							777,000
Potential Proceed from Issuance of Convertible Debt						$ 15,000,000
Gross Proceeds from Convertible Debt						5,500,000						5,500,000
Proceeds from Convertible Debt						4,720,000
Convertible Debt						0
Debt Instrument, Unamortized Discount						$ 4,720,000
Debt Instrument, Term						30 years
Registration Payment Arrangement, Gains and Losses												(1,100,000)
Registration Payment								$ 220,000
Repayments of Debt				$ 7,500,000								7,500,000
Class of Warrant or Right, Cancelled During Period,Value												159,000
Gain (Loss) on Extinguishment of Debt												$ (795,000)
Thirty-Year Debentures [Member] | Series B Warrant [Member]
Residual Fair Value of Warrants						$ 897,000
Thirty-Year Debentures [Member] | Series A Warrant [Member]
Residual Fair Value of Warrants						3,385,000
Payment After Approval of Authorities [Member]
Potential Proceed from Issuance of Convertible Debt						9,500,000
Thirty-Year Debentures, Beneficial Conversion Feature [Member]
Debt Instrument, Convertible, Beneficial Conversion Feature						$ 438,000
Boyalife Investment Inc. [Member]
Gross Proceeds from Financing Transaction							$ 15,000,000
Stock Issued During Period, Shares, New Issues							735,294
Sale of Stock, Price Per Share				$ 3.40			$ 3.40
Stock Issued During Period, Value, New Issues							$ 2,500,000
Debt Instrument, Face Amount				$ 12,500,000			$ 12,500,000