Note 14 Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Segment Reporting Information [Line Items]
Net Revenues	$ 80,857	$ 101,778
Power Semiconductors [Member]
Segment Reporting Information [Line Items]
Net Revenues	59,582	76,464
Integrated Circuits [Member]
Segment Reporting Information [Line Items]
Net Revenues	15,599	18,111
System and RF Semiconductors [Member]
Segment Reporting Information [Line Items]
Net Revenues	5,676	7,203
United States [Member]
Segment Reporting Information [Line Items]
Net Revenues	24,922	27,705
France [Member] | Europe and Middle East [Member]
Segment Reporting Information [Line Items]
Net Revenues	1,573	2,031
Germany [Member] | Europe and Middle East [Member]
Segment Reporting Information [Line Items]
Net Revenues	9,157	13,416
United Kingdom [Member] | Europe and Middle East [Member]
Segment Reporting Information [Line Items]
Net Revenues	7,124	8,002
China [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Revenues	13,384	18,565
Japan [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Revenues	1,828	2,088
Korea [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Revenues	2,243	3,945
Malaysia [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Revenues	1,303	1,120
Singapore [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Revenues	2,645	2,484
Taiwan [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Revenues	1,224	2,232
India [Member] | Rest of the World [Member]
Segment Reporting Information [Line Items]
Net Revenues	1,802	2,829
Other Geographic Regions [Member] | Europe and Middle East [Member]
Segment Reporting Information [Line Items]
Net Revenues	10,250	14,140
Other Geographic Regions [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Revenues	1,355	1,369
Other Geographic Regions [Member] | Rest of the World [Member]
Segment Reporting Information [Line Items]
Net Revenues	$ 2,047	$ 1,852