SIGNIFICANT CUSTOMERS, CONCENTRATION OF CREDIT RISK AND GEOGRAPHIC INFORMATION Net Revenues By Geographic Area (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenues	$ 28,671	$ 27,151	$ 25,592	$ 27,083	$ 26,875	$ 26,418	$ 24,753	$ 25,727	$ 108,497	$ 103,773	$ 119,483
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenues									25,284	28,454	41,559
China, including Hong Kong
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenues									31,653	32,545	30,786
Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenues									23,649	17,430	15,871
Other Asia Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenues									14,258	11,479	15,603
Europe, Middle East and Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenues									$ 13,653	$ 13,865	$ 15,664