Represents number of shares issued to acquiree for each share held by acquiree.

No definition available.

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Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

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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.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

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The cash inflow from the additional capital contribution to the entity.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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

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Number of new stock issued during the period.

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Nature of the Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended		12 Months Ended
	May 26, 2020	May 06, 2019	Jun. 30, 2020	Jun. 29, 2019	Jun. 30, 2020	Jun. 29, 2019	Dec. 28, 2019
Convertible preferred stock conversion ratio					3.5-for-one
Percentage of equity interests			100.00%		100.00%
Discounts and issuance costs of stock issued			$ 628	$ 5,966
Net loss					$ (17,349)	$ (16,090)	$ (33,500)
Accumulated deficit			(386,832)		(386,832)		$ (369,483)
Cash equivalents and marketable securities			$ 139,400		$ 139,400
IPO [Member]
Issue and sale of shares of common stock		6,543,500
Net proceeds from initial public offering		$ 91,400
Discounts and issuance costs of stock issued		$ 6,000
Over-Allotment Option [Member]
Issue and sale of shares of common stock	750,000	853,500
Underwritten Public Offering [Member]
Issue and sale of shares of common stock	5,750,000
Discounts and issuance costs of stock issued	$ 600
Net proceeds from public offering	$ 75,000