Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Organization and Description of Business (Policies)
Notes Tables
Notes Details

Marketable Securities - Marketable Available-for-Sale Securities (Detail)

v3.6.0.2

Marketable Securities - Marketable Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 6,500	$ 33,795
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	(21)
Estimated Fair Value	6,499	33,774
Corporate Debt Securities [Member] \| Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,205	21,671
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	(17)
Estimated Fair Value	2,204	21,654
Asset-backed Securities [Member] \| Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		4,623
Gross Unrealized Gains		0
Gross Unrealized Losses		(2)
Estimated Fair Value		4,621
Commercial Paper [Member] \| Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,295	5,992
Gross Unrealized Gains	0	0
Estimated Fair Value	$ 4,295	5,992
Government Debt Securities [Member] \| Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		1,509
Gross Unrealized Gains		0
Gross Unrealized Losses		(2)
Estimated Fair Value		$ 1,507

- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

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- Definition

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+ 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 (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

Reference 2: 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ 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)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562

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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.

+ References

No definition available.

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