Note 2. Investments and Restricted Cash (Detail) (USD $)			3 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2012 Unrealized Losses [Member]	Mar. 31, 2012 Unrealized Gains [Member]
Long-term Investments	$ 3,584,000	$ 3,923,000
Tax Basis of Investments, Cost for Income Tax Purposes	3,500,000	3,500,000
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax			300,000	200,000
Restricted Cash and Cash Equivalents, Noncurrent	$ 866,000	$ 866,000