Balance Sheet Details (Details Textual) (USD $)	3 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Balance Sheet Details (Textual) [Abstract]
Net unrealized gain	$ 8,000
Product warranty description	one to three years of coverage for products following the date of purchase
Cash equivalents and marketable securities held at bank	18,000,000
Amount borrowed against the facility	7,000,000
Outstanding borrowings under the credit facility	4,800,000
Restricted cash	661,000	0
Restricted marketable securities	$ 4,161,000	$ 0
Minimum [Member]
Balance Sheet Details [Line Items]
Product warranty period	1 year
Maximum [Member]
Balance Sheet Details [Line Items]
Product warranty period	3 years

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- Definition

Cash equivalents and marketable securities held at bank.

+ References

No definition available.

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- Definition

Product warranty coverage period.

+ References

No definition available.

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- Definition

The net amount of gross unrealized gains (losses) for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (d)

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- Definition

Amount borrowed under the credit facility as of the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale which are intended to be held for less than one year or the normal operating cycle, whichever is longer and that are pledged to one or more secured parties who have the right to buy, sell, or re-pledge the collateral.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 9

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-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Section 563c.102

-Paragraph 6

-Subparagraph a

-Chapter V

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

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-Publisher FASB

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-SubTopic 10

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-Name Accounting Standards Codification

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph b

-Article 4

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-BRD

-Paragraph 80

-Subparagraph Exhibit 4-8, 3

-IssueDate 2006-05-01

-Chapter 4

-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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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- Definition

Describes the nature of the product warranty, including the approximate term of the product warranty, how the product warranty arose, and the events or circumstances that would require the warrantor to perform under the product warranty.

+ References

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

-Publisher FASB

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-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (a)

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-Name FASB Interpretation (FIN)

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-Paragraph 13

-Subparagraph a

-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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