Agreements with SK hynix and Micron (Details) - USD ($) $ in Millions	Jun. 18, 2015	Dec. 09, 2013	Jun. 11, 2013	Sep. 30, 2015
SK hynix [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
License Agreement, Term of Agreement	6 years		5 years
License Agreement, Average Amount to be Paid Quarterly				$ 12.0
Future Receivables				432.0
Micron [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
License Agreement, Term of Agreement		7 years
Amount to be paid quarterly				10.0
Future Receivables				204.5
Maximum [Member] \| SK hynix [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount to be paid quarterly				16.0
Minimum [Member] \| SK hynix [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount to be paid quarterly				$ 8.0