Cash Equivalents and Marketable Securities - Schedule of Cash Equivalents and Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Cash Cash Equivalents And Investments [Line Items]
Amortized Cost	$ 0	$ 19,577
Fair Value	0	19,574
Unrealized Gain/(Loss)	0	(3)
Less amounts classified as cash equivalents, Amortized Cost	(6,806)	(17,717)
Less amounts classified as cash equivalents, Fair Value	(6,806)	(17,717)
Less amounts classified as cash equivalents, Unrealized Gain/(Loss)	0	0
Money Market Funds [Member]
Cash Cash Equivalents And Investments [Line Items]
Amortized Cost	6,806	12,674
Fair Value	6,806	12,674
Unrealized Gain/(Loss)	0	0
Less amounts classified as cash equivalents, Fair Value	(6,806)	(12,674)
Corporate Debt Securities [Member]
Cash Cash Equivalents And Investments [Line Items]
Amortized Cost	0	24,620
Fair Value	0	24,617
Unrealized Gain/(Loss)	0	(3)
Less amounts classified as cash equivalents, Fair Value	0	(24,617)
Total [Member]
Cash Cash Equivalents And Investments [Line Items]
Amortized Cost	6,806	37,294
Fair Value	6,806	37,291
Unrealized Gain/(Loss)	$ 0	$ (3)

Cash Cash Equivalents And Investments [Line Items]

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- Definition

Cash Equivalents Amortized Cost

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- Definition

Cash Equivalents Unrealized Gain Loss

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- Definition

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

+ References

No definition available.

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

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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or 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=51813488&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=49167202&loc=d3e26626-111562

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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