Available for sale securities non current maturity period.

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- Definition

Available for sale securities non current minimum liquidating period.

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Discover Period Under Collaboration Agreement

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

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- Definition

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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-Name Accounting Standards Codification

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-SubTopic 10

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-Paragraph 9

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Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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No definition available.

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- Definition

Description of financial instruments, excluding certain derivatives, with off-balance sheet credit risk (for example, standby letters of credit or financial guarantees), including (1) information about the (shared) activity, region or economic characteristic that identifies the concentration, (2) the face or contract amount of the instrument, (3) the nature and terms of the instrument, including the market risk, cash requirements and accounting policies for it, (4) the maximum amount of loss due to credit risk that would be incurred if the counterparties failed completely to perform according to the terms of the contracts, and any security or collateral that proved to be of no value, (5) the entity's policy of requiring collateral or other security to support financial instruments subject to credit risk, information about access to collateral or other security, and a brief description of the security supporting those financial instruments, and (6) the policy of entering into and a brief description of master netting arrangements to mitigate the credit risk, and the extent to which such arrangements would reduce the maximum amount of loss due to credit risk.

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 20

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Description of credit risk that arises from having significant balances in excess of the Federal Deposit Insurance Corporation or other insurance limits on deposits in financial institutions.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Subparagraph (h)(1)(i)

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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-Name Accounting Standards Codification

-Topic 820

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
	Apr. 30, 2010	Dec. 31, 2014 Segment Securities	Dec. 31, 2013 Securities	Dec. 31, 2012
Significant Of Accounting Policies [Line Items]
Tax benefits related to stock based compensation		$ 0	$ 0	$ 0
Significant uncertain tax positions		0us-gaap_UnrecognizedTaxBenefits	0us-gaap_UnrecognizedTaxBenefits
Realized gains or losses on marketable securities		0	0	0
Minimum period to liquidate		12 months	12 months
Debt securities in an unrealized loss position		92	33
Aggregate fair value of debt securities in an unrealized loss position		236,900,000	31,700,000
Concentration of credit risk		The Company has not experienced any credit losses in such accounts and does not believe it is exposed to any significant credit risk on these funds
Off- balance sheet concentrations of credit risk		The Company has no off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements
Financial assets or liabilities that were classified as Level 3		0	0
Transfers of assets from Level 1 to Level 2		0	0
Transfers of assets from Level 2 to Level 1		0	0
Transfers of liabilities from Level 1 to Level 2		0	0
Transfers of liabilities from Level 2 to Level 1		0	0
Initial discovery period under collaboration	2 years
Number of geographic segment in which Company operates		1us-gaap_NumberOfOperatingSegments
Level 3 [Member]
Significant Of Accounting Policies [Line Items]
Financial assets classified as Level 3		0	0
Financial liabilities classified as Level 3		$ 0	$ 0
Maximum [Member]
Significant Of Accounting Policies [Line Items]
Investment maturity period		2 years	2 years
Initial discovery period under collaboration			5 years
Minimum [Member]
Significant Of Accounting Policies [Line Items]
Investment maturity period		1 year	1 year
Initial discovery period under collaboration			4 years