Agreements with SK hynix and Micron (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended	16 Months Ended	3 Months Ended	16 Months Ended	3 Months Ended	16 Months Ended	3 Months Ended	10 Months Ended	3 Months Ended	10 Months Ended	3 Months Ended	10 Months Ended
Sep. 30, 2014 SK hynix [Member]	Jun. 30, 2014 SK hynix [Member]	Mar. 31, 2014 SK hynix [Member]	Sep. 30, 2014 SK hynix [Member]	Sep. 30, 2014 SK hynix [Member] Royalty revenue	Jun. 30, 2014 SK hynix [Member] Royalty revenue	Mar. 31, 2014 SK hynix [Member] Royalty revenue	Sep. 30, 2014 SK hynix [Member] Royalty revenue	Sep. 30, 2014 SK hynix [Member] Gain from settlement	Jun. 30, 2014 SK hynix [Member] Gain from settlement	Mar. 31, 2014 SK hynix [Member] Gain from settlement	Sep. 30, 2014 SK hynix [Member] Gain from settlement	Sep. 30, 2014 Micron [Member]	Jun. 30, 2014 Micron [Member]	Mar. 31, 2014 Micron [Member]	Sep. 30, 2014 Micron [Member]	Sep. 30, 2014 Micron [Member] Royalty revenue	Jun. 30, 2014 Micron [Member] Royalty revenue	Mar. 31, 2014 Micron [Member] Royalty revenue	Sep. 30, 2014 Micron [Member] Royalty revenue	Sep. 30, 2014 Micron [Member] Gain from settlement	Jun. 30, 2014 Micron [Member] Gain from settlement	Mar. 31, 2014 Micron [Member] Gain from settlement	Sep. 30, 2014 Micron [Member] Gain from settlement
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cash Received to date in 2014	$ 12.0	$ 12.0	$ 12.0	$ 60.0	$ 11.8	$ 11.8	$ 11.8	$ 59.1	$ 0.2	$ 0.2	$ 0.2	$ 0.9	$ 10.0	$ 10.0	$ 10.0	$ 35.5	$ 9.7	$ 9.7	$ 9.7	$ 34.3	$ 0.3	$ 0.3	$ 0.3	$ 1.2
Estimated to Be Received in Remainder of 2014	12.0			12.0	11.8			11.8	0.2			0.2	10.0			10.0	9.7			9.7	0.3			0.3
Estimated to Be Received in 2015	48.0			48.0	47.3			47.3	0.7			0.7	40.0			40.0	38.7			38.7	1.3			1.3
Estimated to Be Received in 2016	48.0			48.0	47.9			47.9	0.1			0.1	40.0			40.0	39.5			39.5	0.5			0.5
Estimated to Be Received in 2017	48.0			48.0	48.0			48.0	0			0	40.0			40.0	40.0			40.0	0			0
Estimated to Be Received in 2018	24.0			24.0	24.0			24.0	0			0	40.0			40.0	40.0			40.0	0			0
Estimated to Be Received in 2019 and thereafter													74.5			74.5	74.5			74.5	0			0
Total Estimated Cash receipts	$ 240.0			$ 240.0	$ 238.1			$ 238.1	$ 1.9			$ 1.9	$ 280.0			$ 280.0	$ 276.7			$ 276.7	$ 3.3			$ 3.3

Settlement Agreement, Consideration

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- Definition

Settlement Agreement, Future Receivables, Due In Fifth Full Fiscal Year And Thereafter

+ References

No definition available.

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- Definition

Settlement Agreement, Future Receivables, Due within the first full fiscal year following the date of the most recent balance sheet.

+ References

No definition available.

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- Definition

Settlement Agreement, Future Receivables, Due within the fourth full fiscal year following the date of the most recent balance sheet.

+ References

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Settlement Agreement, Future Receivables, Due within the second full fiscal year following the date of the most recent balance sheet.

+ References

No definition available.

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Settlement Agreement, Future Receivables, Due within the third full fiscal year following the date of the most recent balance sheet.

+ References

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Settlement Agreement, Future Receivables due within the remainder of current fiscal year.

+ References

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- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

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