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Revenue - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018
Disaggregation Of Revenue [Line Items]
Amount of revenue recognized	$ 105,630,000	$ 110,347,000	$ 203,717,000	$ 213,264,000
Aggregate value of remaining performance obligation on outstanding contracts	3,647,000		3,647,000
Revenue recognized related to prior periods			0	0
January 1, 2018 Liability Ending Balance [Member]
Disaggregation Of Revenue [Line Items]
Amount of revenue recognized	600,000	600,000	1,500,000	1,600,000
Point in Time Sales [Member]
Disaggregation Of Revenue [Line Items]
Amount of revenue recognized	105,500,000	110,200,000	203,300,000	212,900,000
Over Time Sales [Member]
Disaggregation Of Revenue [Line Items]
Amount of revenue recognized	$ 100,000	$ 200,000	$ 400,000	$ 400,000

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- Definition

Revenue from contract with customer excluding assessed tax related to prior periods.

+ References

No definition available.

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- Definition

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+ References

No definition available.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045

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