Stock-Based Compensation - Additional Information (Detail) - USD ($)		4 Months Ended	12 Months Ended
	Mar. 20, 2015	Dec. 31, 2019	Dec. 31, 2019	Jan. 01, 2019	Jan. 02, 2018	Mar. 20, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recorded	$ 500,000
Weighted average period of recognition			1 year 10 months 20 days
Weighted-average grant date fair value			$ 12.17
Additional shares granted during period (in shares)			531,173
Granted (in shares)			5,000
Unrecognized compensation expense, net		$ 400,000	$ 400,000
Tax withholdings on restricted stock vesting			204,494	168,484
Payments related to employee tax withholding obligations			$ 2,602,000	$ 2,378,000	$ 1,923,000
Number of awards outstanding		1,142,718	1,142,718	1,234,531
Number of stock options outstanding		412,750	412,750	453,250
2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved and authorized for issuance		3,300,000	3,300,000
Common stock authorized and available for grant		704,948	704,948
Stock-based compensation expense recorded			$ 6,300,000	$ 6,100,000	$ 4,900,000
Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of recognition			2 years 5 months 19 days
Weighted-average grant date fair value			$ 12.17	$ 13.88	$ 13.64
Total fair value of awards vested			$ 6,600,000	$ 5,900,000	$ 5,400,000.0
Unrecognized compensation expense, net		$ 9,300,000	9,300,000
Payments related to employee tax withholding obligations			$ 2,600,000	2,400,000
Restricted Shares | 2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Additional shares granted during period (in shares)			531,173
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Total intrinsic value of stock options exercised			$ 29,000	$ 100,000	$ 0
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards outstanding						0