Regulatory Matters - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Banking and Thrift [Abstract]
Required tangible net assets	$ 2,000,000
Tangible net assets, total	11,659,000us-gaap_TangibleCapital
Subsidiary bank's reserve balance	$ 14,334,000	$ 5,916,000

Cash and due from banks balance maintained in federal reserve.

No definition available.

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- Details

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- Definition

Tangible capital as defined in the regulations (generally includes outstanding stock plus retained earnings) for banking institutions subject to Office of Thrift Supervision (OTS) capital requirements.

+ 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)

-URI http://asc.fasb.org/extlink&oid=7881181&loc=d3e65071-112826

Reference 2: 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=7881181&loc=SL5958568-112826

+ Details

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- Definition

The minimum amount of tangible capital required under the regulatory framework for prompt corrective action.

+ References

+ Details

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