Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2012 item	Dec. 31, 2011
Investments
Fair value of equity security investments	$ 4,300,000	$ 5,900,000
Goodwill
Number of reporting units which impairment test results required the second step measurement	2
Percentage of excess of fair value of operating segments over its carrying value	10.00%
Long-term growth rate used to calculate terminal values for each reporting unit (as a percent)	3.00%
Inventory
Raw materials	148,822,000	133,480,000
Work-in-progress	45,733,000	50,951,000
Finished goods	56,578,000	88,421,000
Total inventory	$ 251,133,000	$ 272,852,000