Note 2. Investments and Restricted Cash (Detail) (USD $)	1 Months Ended			9 Months Ended
	Feb. 28, 2011	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2011 Unrealized Losses [Member]	Sep. 30, 2011 Unrealized Gains [Member]	Dec. 31, 2010 Short Term Cost Basis [Member]
Short-term Investments			$ 1,474,000			$ 800,000
Proceeds from Sale of Short-term Investments	1,400,000
Gain (Loss) on Sale of Investments	600,000
Long-term Investments		3,300,000	1,200,000
Tax Basis of Investments, Cost for Income Tax Purposes		3,700,000	200,000
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax				200,000	600,000
Restricted Cash and Cash Equivalents, Noncurrent		$ 926,000	$ 10,314,000