Note 1 - Significant Accounting Policies (Details) - Fair Value of the Company’s Investments by Type (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 6,275	$ 19,421
Accrued Interest	2	48
Gross Unrealized Gains	2	5
Gross Unrealized Losses		1
Estimated Fair Value	6,279	19,473
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,277	8,528
Accrued Interest	2	47
Gross Unrealized Gains	1	2
Gross Unrealized Losses		1
Estimated Fair Value	1,280	8,576
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,998	5,994
Accrued Interest	0	0
Gross Unrealized Gains	1	2
Gross Unrealized Losses	0	0
Estimated Fair Value	4,999	5,996
US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		4,899
Accrued Interest		1
Gross Unrealized Gains		1
Gross Unrealized Losses		0
Estimated Fair Value		$ 4,901