Date when an entity was incorporated

No definition available.

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- Definition

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
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- Definition

Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

No definition available.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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- Definition

Number of new stock issued during the period.

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-Topic 210
-SubTopic 10
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- Definition

Net proceeds from sale of securities.

+ References

No definition available.

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- Definition

Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]

+ References

No definition available.

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Nature of the Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		6 Months Ended	151 Months Ended
	Jul. 02, 2018	Jun. 30, 2018	Dec. 31, 2017	Dec. 29, 2017
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Entity incorporation date		Nov. 22, 2005
Accumulated deficit		$ (321,308)	$ (289,577)
Net proceeds from sale of securities			333,300
Total cash, cash equivalents and marketable securities		75,800
Subsequent Event [Member] \| Public Offering [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Issuance of common stock	9,200,000
Net proceeds from public offering, after underwriting discount, commission and offering expenses	$ 64,600
Share price per share	$ 7.50
Term Loan [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Aggregate principal balance		20,300		$ 20,000
Loan agreement minimum liquidity required		$ 21,000	$ 21,000