Note 3 - Fair Value Measurements (Detail) - Assets at Fair Value (USD $)	Jun. 30, 2012	Dec. 31, 2011
Assets:
Cash equivalents	$ 1,047,000	$ 310,000
Short-term investments	491,000	1,225,000
Restricted short-term investments	1,000,000	0
Total assets at fair value	2,538,000	1,535,000
Fair Value, Inputs, Level 1 [Member]
Assets:
Cash equivalents	1,047,000	310,000
Short-term investments	491,000	1,225,000
Restricted short-term investments	1,000,000
Total assets at fair value	$ 2,538,000	$ 1,535,000