Certain Financial Statement Information - Estimated future amortization expense (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Schedule of estimated future amortization expense of purchased intangible assets
Fiscal Years Ending March 31, 2014	$ 3,906
2015	3,621
2016	3,086
2017	1,339
2018	39
Total	11,991
Cost of Sales [Member]
Schedule of estimated future amortization expense of purchased intangible assets
Fiscal Years Ending March 31, 2014	2,717
2015	2,717
2016	2,717
2017	1,339
2018	39
Total	9,529
Operating Expenses [Member]
Schedule of estimated future amortization expense of purchased intangible assets
Fiscal Years Ending March 31, 2014	1,189
2015	904
2016	369
2017	0
2018	0
Total	$ 2,462