Regulatory Matters - Additional Information (Detail)	Dec. 31, 2014	Dec. 31, 2013
Banking and Thrift [Abstract]
Minimum ratio of tangible capital to total adjusted assets	1.50%	1.50%
Minimum ratio of tier 1 leverage ratio, For capital adequacy purposes	4.00%	4.00%
Minimum ratio of total capital to risk-weighted assets	8.00%	8.00%
Total risk-based capital, To be well capitalized under prompt corrective action Ratio	10.00%	10.00%
Tier 1 risk-based capital, To be well capitalized under prompt corrective action Ratio	6.00%	6.00%

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1H

-Subparagraph (c)(2)

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

+ 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=35709795&loc=SL5958568-112826

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The minimum amount of Tangible Capital divided by tangible assets (Tangible Capital Ratio) as defined in the regulations.

+ References

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

+ References

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

+ References

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