Income Taxes - Reconciliation of Statutory Federal Income Tax Rate (Detail)	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	21.00%	21.00%	21.00%
State income taxes, net of federal income tax benefit	3.70%	4.00%	4.50%
Non-deductible expenses	1.00%	1.60%	0.90%
Florida excess tax refund relating to the Tax Cuts and Jobs Act	(1.00%)
Excess stock-based compensation tax benefits	(1.40%)	(3.70%)	(8.00%)
Research activities credits	(2.30%)	(1.20%)	(0.70%)
Disaster tax credit for hurricane Irma			(0.70%)
Changes related to state rate changes and U.S. tax reform		0.70%	0.40%
Other	(0.10%)	(0.20%)	(0.10%)
Total statutory federal income tax rate	20.90%	22.20%	17.30%

Effective income tax rate reconciliation disaster tax credit.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible expenses.

+ References

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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