Quantitative Range of Significant Unobservable Inputs Used in Calculation of Fair Value of Continent Consideration Liability (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Dec. 30, 2017
Business Acquisition, Contingent Consideration [Line Items]
Fair Value	$ 361	$ 362
Fair Value, Inputs, Level 3 \| Revenue Earnout
Business Acquisition, Contingent Consideration [Line Items]
Valuation technique	Discounted cash flow
Fair Value	$ 361
Fair Value, Inputs, Level 3 \| Revenue Earnout \| Weighted Average
Business Acquisition, Contingent Consideration [Line Items]
Weighted average cost of capital	12.10%

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.

No definition available.

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- Definition

The amount, measured at acquisition-date fair value, of all liabilities assumed that arise from contingencies and were recognized by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Description of the inputs and valuation technique(s) used to measure fair value.

+ References

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