Financial Statement Details - Summary of Marketable Securities Available-for-Sale (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		22,616
Gross Unrealized Gains		5
Gross Unrealized Losses		0
Estimated Fair Value		22,621us-gaap_AvailableForSaleSecurities
Short-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		19,173
Gross Unrealized Gains		5
Gross Unrealized Losses		0
Estimated Fair Value		19,178
Long-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		3,443
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		3,443
Government agency securities \| Short-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years		1 or less
Amortized Cost		2,350
Gross Unrealized Gains		1
Gross Unrealized Losses		0
Estimated Fair Value		2,351
Municipal bonds \| Short-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years		1 or less
Amortized Cost		2,828
Gross Unrealized Gains		1
Gross Unrealized Losses		0
Estimated Fair Value		2,829
Certificates of deposit \| Short-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years		1 or less
Amortized Cost		3,360
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		3,360
Certificates of deposit \| Long-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years		1 to 2
Amortized Cost		1,300
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		1,300
Corporate debentures / bonds \| Short-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years		1 or less
Amortized Cost		10,635
Gross Unrealized Gains		3
Gross Unrealized Losses		0
Estimated Fair Value		10,638
Corporate debentures / bonds \| Long-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years		1 to 2
Amortized Cost		2,143
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		2,143
Minimum \| Certificates of deposit \| Long-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Long Term Investments Maturity Period	1 year	1 year
Minimum \| Corporate debentures / bonds \| Long-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Long Term Investments Maturity Period	1 year	1 year
Maximum \| Certificates of deposit \| Long-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Long Term Investments Maturity Period	2 years	2 years
Maximum \| Corporate debentures / bonds \| Long-term marketable securities
Schedule of Available-for-sale Securities [Line Items]
Long Term Investments Maturity Period	2 years	2 years

Available-for-sale Securities, Accumulated Gross Unrealized Gain, Before Tax

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Available-for-sale Securities, Accumulated Gross Unrealized Loss, Before Tax

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Long term investment maturity period.

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Marketable securities maturity in years.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

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