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Balance Sheet Details - Additional Information (Detail) (USD $) | 6 Months Ended
--- | ---
Jun. 30, 2014 | Jun. 30, 2013
Condensed Financial Statements, Captions [Line Items] |  |
Borrowings under the facility interest rate | 1.00% |
Cash equivalents and marketable securities held at bank | $ 2,600,000 |
Company's unused borrowing capacity under credit facility | 1,900,000 |
Outstanding borrowings under the credit facility | 0 |
Net unrealized gains (losses) | 6,000 |
Provision for excess and obsolete inventory | $ 3,033,000 | $ 1,823,000
Product warranty description | One to three years of warranty coverage for products following the date of purchase |
Minimum [Member] |  |
Condensed Financial Statements, Captions [Line Items] |  |
Product warranty period | 1 year |
Maximum [Member] |  |
Condensed Financial Statements, Captions [Line Items] |  |
Product warranty period | 3 years |

X
- Definition Net amount of accumulated unrealized gains (losses) on investments in available-for-sale securities that are recognized in Accumulated Other Comprehensive Income (AOCI). + References No definition available. + Details
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- Definition Cash equivalents and marketable securities held at bank. + References No definition available. + Details
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- Definition Product warranty coverage period. + References No definition available. + Details
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- Details
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- Definition Charge to cost of goods sold that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28360613&loc=d3e4542-108314 + Details
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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 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -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 19, 22 -Article 5 + Details
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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 -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249 + Details
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