Note 1 - Organization and Significant Accounting Policies (Detail) - Property and Equipment (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Property and Equipment, Amount	$ 33,170	$ 31,864
Less accumulated depreciation	(19,421)	(18,239)
Total net book value	13,749	13,625
Land [Member]
Property and Equipment, Amount	1,440	1,440
Building [Member]
Property and Equipment, Depreciable Life	39 years
Property and Equipment, Amount	4,535	4,535
Building and Building Improvements [Member] | Minimum [Member]
Property and Equipment, Depreciable Life	3 years
Building and Building Improvements [Member] | Maximum [Member]
Property and Equipment, Depreciable Life	39 years
Building and Building Improvements [Member]
Property and Equipment, Amount	4,480	4,448
Field Equipment [Member] | Minimum [Member]
Property and Equipment, Depreciable Life	3 years
Field Equipment [Member] | Maximum [Member]
Property and Equipment, Depreciable Life	4 years
Field Equipment [Member]
Property and Equipment, Amount	17,746	16,429
Computer Equipment [Member] | Minimum [Member]
Property and Equipment, Depreciable Life	2 years
Computer Equipment [Member] | Maximum [Member]
Property and Equipment, Depreciable Life	3 years
Computer Equipment [Member]
Property and Equipment, Amount	3,151	3,529
Furniture and Fixtures [Member] | Minimum [Member]
Property and Equipment, Depreciable Life	3 years
Furniture and Fixtures [Member] | Maximum [Member]
Property and Equipment, Depreciable Life	10 years
Furniture and Fixtures [Member]
Property and Equipment, Amount	1,782	1,451
Vehicles [Member]
Property and Equipment, Depreciable Life	5 years
Property and Equipment, Amount	$ 36	$ 32