Represents the maximum remaining maturity period at time of purchase by the entity for liquid investments classified as cash equivalents.

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- Definition

The entity's cost method equity investments ownership percentage is less than this percentage.

+ Details

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- Definition

The initial remaining maturity period at time of purchase by the entity must be greater than this period for liquid investments to be classified as short-term investments.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The useful life of all finite-lived intangible assets.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 12, 13, 14

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 35

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6904245&loc=d3e15372-109273

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 46

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16373-109275

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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(4))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section BB

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.BB)

-URI http://asc.fasb.org/extlink&oid=6386940&loc=d3e100047-122729

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- Details

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Significant Accounting Policies (Details 2) (USD $)	9 Months Ended		9 Months Ended
Significant Accounting Policies (Details 2) (USD $)	Sep. 30, 2011 Y D entity count	Dec. 31, 2010	Sep. 30, 2011 Patents Y	Sep. 30, 2010 Patents
Short-term investments
Maximum remaining maturity period at time of purchase of liquid investments classified as cash equivalents (in days)	90
Initial remaining maturity period at time of purchase of liquid investments classified as short-term investments, greater than (in days)	90
Entity's cost method equity investments ownership percentage, less than (as a percent)	20.00%
Inventory valuation
Raw materials	$ 2,915,000	$ 2,484,000
Patents
Estimated useful life (in years)			10
Write-off of patent costs to estimated net realizable values			$ 883,000	$ 1,000,000