Restricted Stock Units Issued (Detail) - Restricted Stock Units (RSUs) - $ / shares		9 Months Ended
Oct. 01, 2018	Sep. 30, 2018
Restricted Stock Units
Beginning Restricted Stock Units	53,454	52,224
Restricted Stock Units Granted	11,275	0
Dividend Equivalents Earned		1,230
Restricted Stock Units Settled		0
Ending Restricted Stock Units		53,454
Weighted-Average Stock Price
Beginning Restricted Stock Units	$ 36.47	$ 36.22
Restricted Stock Units Granted		0
Dividend Equivalents Earned		46.87
Restricted Stock Units Settled		0
Ending Restricted Stock Units		$ 36.47

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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