Balance Sheet Details - Summary of Marketable Securities Available-for-Sale (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 29,758	$ 39,241
Gross Unrealized Gains	4	24
Gross Unrealized Losses	(14)	0
Estimated Fair Value	29,748	39,265
Short-term marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	24,437	38,041
Gross Unrealized Gains	4	23
Gross Unrealized Losses	(9)	0
Estimated Fair Value	24,432	38,064
Long-term marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,321	1,200
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(5)	0
Estimated Fair Value	5,316	1,201
Government agency securities [Member] \| Short-term marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years	1 or less	1 or less
Amortized Cost	3,352	3,265
Gross Unrealized Gains	1	1
Gross Unrealized Losses	0	0
Estimated Fair Value	3,353	3,266
Municipal bonds [Member] \| Short-term marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years	1 or less	1 or less
Amortized Cost	5,875	11,246
Gross Unrealized Gains	2	14
Gross Unrealized Losses	0	0
Estimated Fair Value	5,877	11,260
Certificates of deposit [Member] \| Short-term marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years	1 or less	1 or less
Amortized Cost	5,000	6,200
Gross Unrealized Gains	1	5
Gross Unrealized Losses	0	0
Estimated Fair Value	5,001	6,205
Certificates of deposit [Member] \| Long-term marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years	1 to 2	1 to 2
Amortized Cost	2,740	1,200
Gross Unrealized Gains	0	1
Gross Unrealized Losses	0	0
Estimated Fair Value	2,740	1,201
Corporate debentures / bonds [Member] \| Short-term marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years	1 or less	1 or less
Amortized Cost	10,210	17,330
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(9)	0
Estimated Fair Value	10,201	17,333
Corporate debentures / bonds [Member] \| Long-term marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity in Years	1 to 2
Amortized Cost	2,581
Gross Unrealized Gains	0
Gross Unrealized Losses	(5)
Estimated Fair Value	$ 2,576

Marketable securities maturity in years.

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- Definition

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

-Paragraph 1

-Subparagraph (b)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ 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 210.5-02.2)

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- Definition

Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

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- Definition

Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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