The amount of the cost recognized during the period for defined contribution plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

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Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2016	Dec. 30, 2015	Dec. 31, 2014
Defined Contribution Plan Disclosure [Line Items]
Qualified compensation of employees that may be contributed, maximum	25.00%
Benefit contribution	$ 0.6	$ 0.5	$ 0.5
First 3% of Annual Qualified Compensation [Member]
Defined Contribution Plan Disclosure [Line Items]
Percentage of employees' annual qualified compensation matched	3.00%
Employer's matching contribution	100.00%
Next 2 % of Annual Qualified Compensation [Member]
Defined Contribution Plan Disclosure [Line Items]
Percentage of employees' annual qualified compensation matched	2.00%
Employer's matching contribution	50.00%