Segments and Major Customers (Details 3) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Major Customer Disclosure
Revenues	$ 99,134	$ 89,855	$ 291,205	$ 239,038
South Korea
Major Customer Disclosure
Revenues	29,476	32,519	86,736	95,604
USA
Major Customer Disclosure
Revenues	43,532	32,951	123,115	84,835
Japan
Major Customer Disclosure
Revenues	4,933	9,551	18,508	20,449
Europe
Major Customer Disclosure
Revenues	9,160	4,271	17,850	12,362
Canada
Major Customer Disclosure
Revenues	933	1,162	3,353	2,544
SINGAPORE
Major Customer Disclosure
Revenues	4,927	4,429	17,563	13,574
Asia-Other
Major Customer Disclosure
Revenues	$ 6,173	$ 4,972	$ 24,080	$ 9,670