Contingent Liabilities - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 28, 2015	Mar. 29, 2014	Mar. 28, 2015 Location	Mar. 29, 2014	Jun. 28, 2014
Commitments and Contingencies Disclosure [Abstract]
Reserves related to environmental matters	$ 1,100		$ 1,100		$ 900
Expenses related to environmental matters	$ 174us-gaap_EnvironmentalRemediationExpense	$ 70us-gaap_EnvironmentalRemediationExpense	$ 529us-gaap_EnvironmentalRemediationExpense	$ 353us-gaap_EnvironmentalRemediationExpense
Locations with alleged violations			4gk_Locationswithallegedviolations
Locations under audit			8gk_Locationsunderaudit

Number of locations being audited by the U.S. Department of Labor's Office of Federal Contract Compliance Programs

No definition available.

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- Definition

Number of locations with alleged violations by the U.S. Department of Labor's Office of Federal Contract Compliance Programs

+ References

No definition available.

+ Details

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

+ Details

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- Definition

The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13296-110859

+ Details

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Balance Type:	debit
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