Estimate of Annual Preventable Hospital Deaths Prevented by 2020

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Related Party Transactions - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Jul. 31, 2015 USD ($)	Dec. 29, 2018 USD ($) ft² death	Dec. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Related Party Transaction [Line Items]
Patent and Licensing Fee - Aggregate	$ 2,400,000
Property Plant and Equipment, Occupied Square Feet \| ft²		16,830
Capitalized Software Development Costs for Software Sold to Customers		$ 700,000	$ 200,000	$ 0
Estimate of annual preventable hospital deaths prevented by 2020 (more than) \| death		200,000
Not for Profit Organization
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		$ 2,000,000	0	5,000,000
Not for Profit Social Welfare Organization
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		0	0	20,000
Variable Interest Entity, Primary Beneficiary [Member]
Related Party Transaction [Line Items]
Minimum aggregate royalty payments		10,900,000	8,000,000	6,400,000
Payment for Administrative Fees		200,000	200,000	200,000
Variable Interest Entity, Primary Beneficiary [Member] \| Not for Profit Organization
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		207,530	1,300	200,271
Minimum \| Variable Interest Entity, Primary Beneficiary [Member]
Related Party Transaction [Line Items]
Minimum aggregate royalty payments		5,000,000
Reimbursement Fee [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party		200,000	100,000
Cercacor Laboratories
Related Party Transaction [Line Items]
Related Party Transaction, Other Revenues from Transactions with Related Party		100,000	100,000	100,000
Operating Leases, Income Statement, Sublease Revenue		400,000	400,000	$ 300,000
Related Party Transaction, Due from (to) Related Party		$ 2,900,000	$ 1,500,000