Net Income per Share - Computation of Earnings Per Share, Basic (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 26, 2020	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Dec. 28, 2019	[1]	Sep. 28, 2019	[1]	Jun. 29, 2019	[1]	Mar. 30, 2019	[1]	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 32,817	$ 80,768	$ 60,141	$ 18,234	$ 13,762		$ 44,729		$ 27,856		$ 23,694		$ 191,960	$ 110,041	$ 92,663
Allocation of net income for basic:
Allocation of net income for basic common stock													$ 191,960	$ 110,041	$ 92,663
Weighted average number of shares for basic:
Weighted-average number of common shares - basic													12,204	11,886	11,733
Net income per share for basic:
Net income per common share - basic	$ 2.68	$ 6.61	$ 4.93	$ 1.50	$ 1.13		$ 3.70		$ 2.39		$ 2.04		$ 15.73	$ 9.26	$ 7.90
Common Class A
Allocation of net income for basic:
Allocation of net income for basic common stock													$ 153,106	$ 82,474	$ 68,080
Weighted average number of shares for basic:
Weighted-average number of common shares - basic													9,734	8,908	8,620
Net income per share for basic:
Net income per common share - basic													$ 15.73	$ 9.26	$ 7.90
Common Class B
Allocation of net income for basic:
Allocation of net income for basic common stock													$ 37,690	$ 26,600	$ 23,710
Weighted average number of shares for basic:
Weighted-average number of common shares - basic													2,396	2,873	3,002
Net income per share for basic:
Net income per common share - basic													$ 15.73	$ 9.26	$ 7.90
Unvested participating shares
Allocation of net income for basic:
Allocation of net income for basic unvested participating shares													$ 1,164	$ 967	$ 873
Weighted average number of shares for basic:
Weighted-average number of common shares - basic													74	105	111

[1] During the second, third and fourth quarter of 2019, the Company recorded $1.9 million, $5.9 million and $2.1 million in non-reoccurring transaction fees related to the Dogfish Head Transaction, respectively.