Deposits - Summary of interest expense on deposits (Detail 1) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deposits [Abstract]
NOW and SuperNOW	$ 11,608	$ 11,300	$ 15,754
Money Market	9,965	10,618	25,914
Savings	37,537	55,591	106,424
Certificates of Deposit, $100,000 or more	523,472	373,880	459,130
Other time deposits	1,310,732	1,562,938	2,003,684
Interest expense	$ 1,893,314	$ 2,014,327	$ 2,610,906

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Aggregate amount of all interest expense on domestic deposit liabilities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.6)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 6

-Article 9

+ Details

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- Definition

Amount of interest expense on domestic certificates of deposit liabilities.

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- Definition

Amount of interest expense on domestic money market demand account deposit liabilities.

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+ Details

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- Definition

Amount of interest expense on domestic notice of withdrawal demand deposit liabilities.

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- Definition

Amount of interest expense on domestic time deposit liabilities other than certificates of liabilities.

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- Definition

Amount of interest expense on domestic savings deposit liabilities.

+ References

+ Details

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