A valuation allowance for financing receivables that are expected to be uncollectible.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.11)

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

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Loans and Allowance - Total Allowance by Loan Segment (Detail) (USD $)	3 Months Ended												12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses	$ 746	$ 125	$ 112	$ 38	$ 260				$ 100	$ 150			$ 1,020,876	$ 260,000	$ 250,000
Individually evaluated for impairment, Balance in allowance	1,270,159												1,270,159
Loans Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of year				2,972,019				3,307,920				3,930,924	2,972,019	3,307,920	3,930,924
Provision for credit losses													1,020,876	260,000	250,000
Recoveries													471,330	437,502	392,275
Loans charged off													(1,346,355)	(1,033,403)	(1,265,279)
Balance, end of year	3,117,870				2,972,019				3,307,920				3,117,870	2,972,019	3,307,920
Individually evaluated for impairment, Balance in allowance	1,270,159				1,163,567				1,314,777				1,270,159	1,163,567	1,314,777
Individually evaluated for impairment, Related loan balance	6,445,676				5,908,796				7,398,293				6,445,676	5,908,796	7,398,293
Collectively evaluated for impairment, Balance in allowance	1,847,711				1,808,452				1,993,143				1,847,711	1,808,452	1,993,143
Collectively evaluated for impairment, Balance in allowance	271,784,827				268,918,682				246,624,399				271,784,827	268,918,682	246,624,399
Loans Receivable \| Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of year				412,909				541,916				557,169	412,909	541,916	557,169
Provision for credit losses													(4,580)	46,303	29,282
Recoveries													6,440	26,804	10,558
Loans charged off													(29,138)	(202,114)	(55,093)
Balance, end of year	385,631				412,909				541,916				385,631	412,909	541,916
Individually evaluated for impairment, Balance in allowance	252,500				278,786				451,126				252,500	278,786	451,126
Individually evaluated for impairment, Related loan balance	252,500				278,786				796,511				252,500	278,786	796,511
Collectively evaluated for impairment, Balance in allowance	133,131				134,123				90,790				133,131	134,123	90,790
Collectively evaluated for impairment, Balance in allowance	3,266,252				3,893,961				4,104,596				3,266,252	3,893,961	4,104,596
Loans Receivable \| Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of year				898,362				1,183,240				2,012,962	898,362	1,183,240	2,012,962
Provision for credit losses													(448,027)	(374,067)	(919,161)
Recoveries													128,068	89,189	89,439
Loans charged off													(243,394)
Balance, end of year	335,009				898,362				1,183,240				335,009	898,362	1,183,240
Individually evaluated for impairment, Balance in allowance	148,791				550,794				807,735				148,791	550,794	807,735
Individually evaluated for impairment, Related loan balance	2,155,816				3,364,193				4,980,503				2,155,816	3,364,193	4,980,503
Collectively evaluated for impairment, Balance in allowance	186,218				347,568				375,505				186,218	347,568	375,505
Collectively evaluated for impairment, Balance in allowance	63,486,816				65,414,415				67,898,601				63,486,816	65,414,415	67,898,601
Loans Receivable \| Consumer and Indirect
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of year				1,187,604				1,057,531				888,614	1,187,604	1,057,531	888,614
Provision for credit losses													601,522	468,559	357,622
Recoveries													331,108	313,795	286,564
Loans charged off													(839,012)	(652,281)	(475,269)
Balance, end of year	1,281,222				1,187,604				1,057,531				1,281,222	1,187,604	1,057,531
Individually evaluated for impairment, Balance in allowance	186,226				178,657				20,000				186,226	178,657	20,000
Individually evaluated for impairment, Related loan balance	1,106,217				636,174				76,251				1,106,217	636,174	76,251
Collectively evaluated for impairment, Balance in allowance	1,094,996				1,008,947				1,037,531				1,094,996	1,008,947	1,037,531
Collectively evaluated for impairment, Balance in allowance	82,996,925				72,594,259				66,020,034				82,996,925	72,594,259	66,020,034
Loans Receivable \| Residential Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of year				593,463				392,506				595,812	593,463	392,506	595,812
Provision for credit losses													805,261	372,251	525,897
Recoveries													5,714	7,714	5,714
Loans charged off													(234,811)	(179,008)	(734,917)
Balance, end of year	1,169,627				593,463				392,506				1,169,627	593,463	392,506
Individually evaluated for impairment, Balance in allowance	682,642				155,330				35,916				682,642	155,330	35,916
Individually evaluated for impairment, Related loan balance	2,931,143				1,629,643				1,545,028				2,931,143	1,629,643	1,545,028
Collectively evaluated for impairment, Balance in allowance	486,985				438,133				356,590				486,985	438,133	356,590
Collectively evaluated for impairment, Balance in allowance	122,034,834				127,016,047				108,601,168				122,034,834	127,016,047	108,601,168
Loans Receivable \| Unallocated
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of year				(120,319)				132,727				(123,633)	(120,319)	132,727	(123,633)
Provision for credit losses													66,700	(253,046)	256,360
Recoveries
Loans charged off
Balance, end of year	(53,619)				(120,319)				132,727				(53,619)	(120,319)	132,727
Individually evaluated for impairment, Balance in allowance
Individually evaluated for impairment, Related loan balance
Collectively evaluated for impairment, Balance in allowance	(53,619)				(120,319)				132,727				(53,619)	(120,319)	132,727
Collectively evaluated for impairment, Balance in allowance