The increase in the number of shares of common stock reserved for future issuance.

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Total amount of certain expenses that are reimbursed to the Variable Interest Entity.

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The aggregate amount related to the patent and licensing fee.

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Amount paid to managing member or general partner, affiliate of managing member or general partner, or affiliate of limited liability company (LLC) or limited partnership (LP) for administrative services provided to the LLC or LP, for example, but not limited to, salaries, rent, or overhead costs.

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The amount of cash paid for royalties during the current period.

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Amount of transactions with related party during the financial reporting period.

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The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

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The amount of costs incurred under a research and development arrangement accounted for as a contract to perform research and development for others.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Variable Interest Entities (VIEs) - Additional Information (Detail)			1 Months Ended		12 Months Ended
	Aug. 07, 2007 shares	Jan. 02, 2007 company	Jul. 31, 2015 USD ($)	Feb. 28, 2009	Dec. 31, 2016 USD ($)	Jan. 02, 2016 USD ($)	Jan. 03, 2015 USD ($)	Dec. 28, 2013 USD ($)	Dec. 29, 2012	Dec. 31, 2011
Variable Interest Entity [Line Items]
Number of Companies with Rights to Intellectual Property \| company		2
Patent and Licensing Fee - Aggregate			$ 2,400,000
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Minimum aggregate royalty payments					$ 6,400,000.0	$ 6,700,000.0	$ 5,500,000.0
Percentage Reimbursed				50.00%					60.00%	50.00%
Total expenses for additional services, material and supplies					0	300,000	3,100,000
Payment for Administrative Fees					200,000	$ 200,000	200,000	$ 200,000
Minimum \| Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Minimum aggregate royalty payments					5,000,000.0
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Percentage Reimbursed						60.00%
Research and Development Arrangement, Contract to Perform for Others, Costs Incurred, Gross							900,000
Development Partner [Member] [Member]
Variable Interest Entity [Line Items]
Related Party Transaction, Amounts of Transaction					$ 255,000	$ 200,000	0
Two Thousand Seven Plan [Member]
Variable Interest Entity [Line Items]
Common Stock Shares Added To Share Reserve \| shares	1,700,000.0
Engineering-related Payroll Expenses [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Research and Development Arrangement, Contract to Perform for Others, Compensation Earned							1,600,000
Research and Development Arrangement, Contract to Perform for Others, Costs Incurred, Gross							$ 1,400,000