Regulatory Matters - Additional Information (Detail)	12 Months Ended
Jun. 30, 2017	Jun. 29, 2017
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common equity Tier 1 capital conservation buffer	2.50%
Capital conservation buffer risk-weighted assets	0.625%
Minimum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CETI capital ratio of risk- weighted assets	4.50%
Tier 1 capital ratio of risk-weighted assets	6.00%	4.00%
Leverage ratio	4.00%

Tier One Capital Conservation Buffer to Risk Weighted Assets Required under Regulatory

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- Definition

Tier one risk based capital to risk weighted assets conservation buffer.

+ References

No definition available.

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- Definition

Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

+ References

No definition available.

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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.

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- Definition

Tier 1 Leverage Capital divided by average assets as defined in the regulations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

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- Definition

Tier 1 capital divided by risk weighted assets as defined by regulations.

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