Inventory (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Inventory Disclosure [Abstract]
Inventory, Various Programs, Gross	$ 38,300,000
Write-downs on excess, obsolete or unmarketable inventory	$ 24,821,000	$ 25,446,000	$ 11,808,000