Business Segments and Major Customers (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Major Customer Disclosure
Revenues	$ 57,530	$ 100,263	$ 176,608	$ 229,004
South Korea
Major Customer Disclosure
Revenues	21,648	24,641	66,363	68,859
Japan
Major Customer Disclosure
Revenues	17,347	19,899	50,818	76,149
United States
Major Customer Disclosure
Revenues	14,309	42,096	45,778	69,897
Canada
Major Customer Disclosure
Revenues	1,983	12,463	5,835	12,758
Asia-Other
Major Customer Disclosure
Revenues	750	167	4,250	330
Europe
Major Customer Disclosure
Revenues	$ 1,493	$ 997	$ 3,564	$ 1,011