Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
OTHER PHYSICAL PROPERTY:
Other physical property, accumulated depreciation	$ 219	$ 203
CURRENT ASSETS:
Receivables, reserves	$ 305	$ 334
COMMON STOCKHOLDERS' EQUITY:
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, authorized (in shares)	46,500,000	46,500,000
Common stock, issued (in shares)	12,918,633	12,791,671
Common stock, outstanding (in shares)	12,918,633	12,791,671
Preferred stock, authorized (in shares)	500,000	500,000
Preferred stock, issued (in shares)	0	0