Shareholders' Equity - Additional Information (Detail)		12 Months Ended
	Sep. 18, 2018 $ / shares shares	Jan. 02, 2021 USD ($) shares	Dec. 28, 2019 USD ($) shares	Dec. 29, 2018 USD ($) Time $ / shares shares	May 22, 2019 USD ($)
Schedule Of Equity [Line Items]
Number of times common stock grants issued, under special employee grants | Time				3
Shares issued to employees, under special employee grants | shares				28,160
Number of shares received by each employee under special employee grants | shares				10
Weighted average grant date fair value per share, issued under special employee grants | $ / shares				$ 20.84
Allocated stock-based compensation expense		$ 5,458,000	$ 3,923,000	$ 3,383,000
Common stock , gross proceeds				$ 161,000,000.0
Common stock underwriting fee , per share | $ / shares				$ 1.15
Proceeds from issuance of common stock				$ 153,000,000.0
Proceeds to prepay outstanding borrowings				152,000,000.0
Payment of offering expenses				447,000
Acquisition of treasury stock		$ 815,000	$ 6,055,000	687,000
Program for Repurchases of Company Common Stock [Member]
Schedule Of Equity [Line Items]
Shares repurchased | shares			393,819
Stock repurchase program, authorized amount					$ 30,000,000
Total cost of common stock repurchased			$ 5,500,000
Underwritten Public Offering [Member]
Schedule Of Equity [Line Items]
Common stock , issued | shares	7,000,000
Common stock, price per share | $ / shares	$ 23.00
Special Employee Grants of Common Stock [Member]
Schedule Of Equity [Line Items]
Allocated stock-based compensation expense				587,000
Restricted Stock [Member]
Schedule Of Equity [Line Items]
Shares repurchased | shares		51,479	34,240
Acquisition of treasury stock		$ 815,000	$ 505,000
Selling, General and Administrative Expenses [Member]
Schedule Of Equity [Line Items]
Allocated stock-based compensation expense		$ 4,800,000	$ 3,200,000	3,400,000
Selling, General and Administrative Expenses [Member] | Special Employee Grants of Common Stock [Member]
Schedule Of Equity [Line Items]
Allocated stock-based compensation expense				$ 587,000