Note 9 - Income Taxes - Approximate Amount of Unused Operating Loss Carry Forwards and Expiration Dates (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Operating Loss Carryforwards	$ 204,862
Expires 2023 [Member]
Operating Loss Carryforwards	7,136
Expires 2024 [Member]
Operating Loss Carryforwards	15,647
Expires 2025 [Member]
Operating Loss Carryforwards	8,168
Expires 2026 [Member]
Operating Loss Carryforwards	7,361
Expires 2028 [Member]
Operating Loss Carryforwards	11,905
Expires 2029 [Member]
Operating Loss Carryforwards	18,547
Expires 2030 [Member]
Operating Loss Carryforwards	18,145
Expires 2031 [Member]
Operating Loss Carryforwards	21,386
Expires 2032 [Member]
Operating Loss Carryforwards	20,558
Expires 2033 [Member]
Operating Loss Carryforwards	10,321
Expires 2034 [Member]
Operating Loss Carryforwards	22,906
Expires 2035 [Member]
Operating Loss Carryforwards	21,338
Expires 2036 [Member]
Operating Loss Carryforwards	$ 21,444