Number of Company's patents found invalid.

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- Definition

Number of respondents with whom a settlement was reached.

+ References

No definition available.

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- Definition

Number of entity's patents that another entity was found not to have infringed.

+ References

No definition available.

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- Definition

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 1

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

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-Publisher FASB

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-Topic 840

-SubTopic 20

-Section 50

-Paragraph 1

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (c)

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Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.25)

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Commitments and Contingencies - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended				12 Months Ended
	Apr. 30, 2014	Jul. 31, 2010 patent	Jul. 31, 2010 Patents	Dec. 31, 2009 Respondent	Sep. 30, 2009 Respondent	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Number of respondents with whom a settlement was reached				5	2
Number of the Company's patents found invalid			2
Number of the Company's patents found invalid		2
Proceeds from Legal Settlements	$ 2,600,000us-gaap_ProceedsFromLegalSettlements
Purchase order outstanding						4,748,000
Total annual rental expense						6,021,000us-gaap_OperatingLeasesRentExpenseNet	5,772,000us-gaap_OperatingLeasesRentExpenseNet	5,806,000us-gaap_OperatingLeasesRentExpenseNet
Total annual rental income						$ 1,794,000	$ 676,000	$ 854,000