Organization and Significant Accounting Policies (Details 4) (USD $)	12 Months Ended
	Dec. 31, 2011 Y	Dec. 31, 2010 Y	Dec. 31, 2009
Licenses
Patents
Estimated useful life, minimum (in years)	3
Estimated useful life, maximum (in years)	15
Intangible assets cost	$ 36,200,000	$ 36,200,000
Accumulated amortization	27,200,000	23,900,000
2012	2,400,000
2013	2,000,000
2014	1,900,000
2015	1,900,000
2016	800,000
Patents
Patents
Intangible assets cost	29,900,000	33,300,000
Accumulated amortization	13,700,000	17,500,000
2012	1,500,000
2013	1,000,000
2014	800,000
2015	600,000
2016	600,000
Estimated useful life (in years)	10
Weighted average remaining amortizable life (in years)	2.6	2.5
Non cash charges related to write-down of patent costs	$ 1,900,000	$ 1,500,000	$ 696,000