Marketable Securities - Schedule of Marketable Securities (Detail) $ in Thousands	Jun. 30, 2016 USD ($)
Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 10,980
Unrealized Losses	(1)
Fair Value	10,979
Cash Equivalents [Member] \| Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,476
Fair Value	8,476
Cash Equivalents [Member] \| Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,504
Unrealized Losses	(1)
Fair Value	2,503
Marketable Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	61,174
Unrealized Gains	8
Unrealized Losses	(6)
Fair Value	61,176
Marketable Securities [Member] \| Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,980
Unrealized Gains	4
Unrealized Losses	(5)
Fair Value	20,979
Marketable Securities [Member] \| Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21,200
Unrealized Gains	1
Unrealized Losses	(1)
Fair Value	21,200
Marketable Securities [Member] \| US Government Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	18,994
Unrealized Gains	3
Fair Value	$ 18,997

This item represents the cost of debt 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.

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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27198-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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