Schedule1 - Registrant's Condensed Financial Statements - Condensed Balance Sheets (Parenthetical) (Detail) - $ / shares	Jun. 29, 2019	Dec. 29, 2018	Dec. 30, 2017
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, authorized (shares)	500,000,000
Series A Preferred stock, par value (usd per share)	$ 0.001	$ 0.001	$ 0.001
Series A Preferred stock, shares authorized (shares)	50,000,000	1	1
Series A Preferred stock, shares issued (shares)	0	1	1
Series A Preferred stock, shares outstanding (shares)	0	1	1
Parent Company
Condensed Balance Sheet Statements, Captions [Line Items]
Series A Preferred stock, par value (usd per share)		$ 0.001	$ 0.001
Series A Preferred stock, shares authorized (shares)		1	1
Series A Preferred stock, shares issued (shares)		1	1
Series A Preferred stock, shares outstanding (shares)		1	1
Common
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, par value (usd per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, authorized (shares)	500,000,000	107,536,215	107,536,215
Common stock, issued (shares)	88,311,764	67,435,288	67,381,104
Common stock, outstanding (shares)	88,311,764	67,435,288	67,381,104
Common \| Parent Company
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, par value (usd per share)		$ 0.001	$ 0.001
Common stock, authorized (shares)		107,536,215	107,536,215
Common stock, issued (shares)		67,381,104	67,435,288
Common stock, outstanding (shares)		67,381,104	67,435,288
Nonvoting Common
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, par value (usd per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, authorized (shares)	0	17,463,785	17,463,785
Common stock, issued (shares)	0	1,038,413	1,038,413
Common stock, outstanding (shares)	0	1,038,413	1,038,413
Nonvoting Common \| Parent Company
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, par value (usd per share)		$ 0.001	$ 0.001
Common stock, authorized (shares)		17,463,785	17,463,785
Common stock, issued (shares)		1,038,413	1,038,413
Common stock, outstanding (shares)		1,038,413	1,038,413

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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