Loans and Allowance for Loan Losses, Part II (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum Balance Of Loans For Which Credit Quality Analysis Is Performed	$ 100,000
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	2,141,000		1,133,000
60-89 days Past Due	332,000		321,000
90 Days or More Past Due	1,405,000		1,433,000
Total Past Due	3,878,000		2,887,000
Current	1,050,278,000		1,059,519,000
Total Loans Receivable	1,054,156,000		1,062,406,000
Total Loans 90 days & Accruing	0		0
Number of days past due when interest is not accrued	ninety days
Period of satisfactory performance before returning to accrual status	not less than six months
Loans with a specific allowance [Abstract]
Recorded Balance	1,546,000		1,407,000
Unpaid Principal Balance	2,111,000		4,261,000
Specific Allowance	625,000		263,000
Loans without a specific allowance [Abstract]
Recorded Balance	3,111,000		3,133,000
Unpaid Principal Balance	8,765,000		7,902,000
Total Loans [Abstract]
Recorded Balance	4,657,000		4,540,000
Unpaid Principal Balance	10,876,000		12,163,000
Average recorded investment and interest income recognized [Abstract]
Average investment in impaired loans	4,699,000	5,523,000
Interest income recognized	5,000	5,000
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	4,168,000		4,105,000
Interest Lost on Nonaccrual Loans	97,000,000	37,000,000
Troubled Debt Restructuring [Abstract]
Troubled Debt Restructurings Balance	2,502,000		2,860,000
Troubled Debt Restructuring, Allowance	220,000		234,000
Financing Receivable Modifications Performing Recorded Investment	488,000		435,000
Recorded Balance of Troubled Debt Restructurings [Abstract]
Financing Receivables, Modifications during Period, Number	4	2
Financing Receivables, Modifications during Period, Balance	66,000	207,000
Subsequent Default, Number of Days Past Due	90 days
Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	1,017,986,000		1,026,901,000
Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	25,857,000		25,696,000
Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	10,313,000		9,809,000
Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Construction and land development
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	0		297,000
60-89 days Past Due	0		25,000
90 Days or More Past Due	0		0
Total Past Due	0		322,000
Current	27,152,000		21,305,000
Total Loans Receivable	27,152,000		21,627,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	419,000		785,000
Unpaid Principal Balance	984,000		2,960,000
Specific Allowance	33,000		43,000
Loans without a specific allowance [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Total Loans [Abstract]
Recorded Balance	419,000		785,000
Unpaid Principal Balance	984,000		2,960,000
Average recorded investment and interest income recognized [Abstract]
Average investment in impaired loans	419,000	1,446,000
Interest income recognized	0	0
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	418,000		785,000
Troubled Debt Restructuring [Abstract]
Troubled Debt Restructurings Balance	419,000		785,000
Construction and land development \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	26,733,000		20,842,000
Construction and land development \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Construction and land development \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	419,000		785,000
Construction and land development \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Agricultural real estate
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	106,000		0
60-89 days Past Due	0		0
90 Days or More Past Due	0		0
Total Past Due	106,000		0
Current	109,348,000		110,193,000
Total Loans Receivable	109,454,000		110,193,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Specific Allowance	0		0
Loans without a specific allowance [Abstract]
Recorded Balance	96,000		73,000
Unpaid Principal Balance	101,000		235,000
Total Loans [Abstract]
Recorded Balance	96,000		73,000
Unpaid Principal Balance	101,000		235,000
Average recorded investment and interest income recognized [Abstract]
Average investment in impaired loans	96,000	101,000
Interest income recognized	1,000	0
Loans Receivable, Modifications, Still Accruing Interest	67,000
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	29,000		29,000
Troubled Debt Restructuring [Abstract]
Troubled Debt Restructurings Balance	67,000		44,000
Financing Receivable Modifications Performing Recorded Investment	67,000		44,000
Recorded Balance of Troubled Debt Restructurings [Abstract]
Financing Receivables, Modifications during Period, Number	1
Financing Receivables, Modifications during Period, Balance	23,000
Agricultural real estate \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	106,383,000		107,976,000
Agricultural real estate \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	1,908,000		1,036,000
Agricultural real estate \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	1,163,000		1,181,000
Agricultural real estate \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
1-4 Family residential properties
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	384,000		201,000
60-89 days Past Due	77,000		224,000
90 Days or More Past Due	394,000		385,000
Total Past Due	855,000		810,000
Current	174,337,000		181,111,000
Total Loans Receivable	175,192,000		181,921,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	203,000		67,000
Unpaid Principal Balance	203,000		134,000
Specific Allowance	14,000		0
Loans without a specific allowance [Abstract]
Recorded Balance	1,063,000		1,156,000
Unpaid Principal Balance	2,915,000		2,866,000
Total Loans [Abstract]
Recorded Balance	1,266,000		1,223,000
Unpaid Principal Balance	3,118,000		3,000,000
Average recorded investment and interest income recognized [Abstract]
Average investment in impaired loans	1,292,000	1,083,000
Interest income recognized	2,000	2,000
Loans Receivable, Modifications, Still Accruing Interest	344,000	307,000
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	922,000		878,000
Troubled Debt Restructuring [Abstract]
Troubled Debt Restructurings Balance	422,000		503,000
Financing Receivable Modifications Performing Recorded Investment	344,000		345,000
Recorded Balance of Troubled Debt Restructurings [Abstract]
Financing Receivables, Modifications during Period, Number	1	2
Financing Receivables, Modifications during Period, Balance	11,000	207,000
1-4 Family residential properties \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	171,059,000		177,764,000
1-4 Family residential properties \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	1,128,000		1,187,000
1-4 Family residential properties \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	3,005,000		2,970,000
1-4 Family residential properties \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Multifamily residential properties
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	0		0
60-89 days Past Due	0		0
90 Days or More Past Due	0		0
Total Past Due	0		0
Current	52,682,000		53,129,000
Total Loans Receivable	52,682,000		53,129,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Specific Allowance	0		0
Loans without a specific allowance [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Total Loans [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Multifamily residential properties \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	52,100,000		52,793,000
Multifamily residential properties \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	251,000		0
Multifamily residential properties \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	331,000		336,000
Multifamily residential properties \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Commercial real estate
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	1,408,000		60,000
60-89 days Past Due	0		32,000
90 Days or More Past Due	891,000		945,000
Total Past Due	2,299,000		1,037,000
Current	373,318,000		378,567,000
Total Loans Receivable	375,617,000		379,604,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	470,000		472,000
Unpaid Principal Balance	470,000		986,000
Specific Allowance	134,000		136,000
Loans without a specific allowance [Abstract]
Recorded Balance	1,605,000		1,640,000
Unpaid Principal Balance	4,189,000		3,808,000
Total Loans [Abstract]
Recorded Balance	2,075,000		2,112,000
Unpaid Principal Balance	4,659,000		4,794,000
Average recorded investment and interest income recognized [Abstract]
Average investment in impaired loans	2,084,000	2,185,000
Interest income recognized	1,000	1,000
Loans Receivable, Modifications, Still Accruing Interest	37,000	39,000
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	2,038,000		2,074,000
Troubled Debt Restructuring [Abstract]
Troubled Debt Restructurings Balance	1,261,000		1,283,000
Financing Receivable Modifications Performing Recorded Investment	37,000		37,000
Commercial real estate \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	354,391,000		357,873,000
Commercial real estate \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	18,372,000		18,817,000
Commercial real estate \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	2,854,000		2,914,000
Commercial real estate \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Agricultural loans
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	10,000		16,000
60-89 days Past Due	0		20,000
90 Days or More Past Due	0		0
Total Past Due	10,000		36,000
Current	56,965,000		68,262,000
Total Loans Receivable	56,975,000		68,298,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Specific Allowance	0		0
Loans without a specific allowance [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Total Loans [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	0		0
Agricultural loans \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	55,578,000		67,619,000
Agricultural loans \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	501,000		0
Agricultural loans \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	896,000		679,000
Agricultural loans \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Commercial and industrial loans
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	181,000		228,000
60-89 days Past Due	1,000		10,000
90 Days or More Past Due	118,000		98,000
Total Past Due	300,000		336,000
Current	233,041,000		223,444,000
Total Loans Receivable	233,341,000		223,780,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	203,000		83,000
Unpaid Principal Balance	203,000		181,000
Specific Allowance	193,000		84,000
Loans without a specific allowance [Abstract]
Recorded Balance	305,000		249,000
Unpaid Principal Balance	1,199,000		933,000
Total Loans [Abstract]
Recorded Balance	508,000		332,000
Unpaid Principal Balance	1,402,000		1,114,000
Average recorded investment and interest income recognized [Abstract]
Average investment in impaired loans	514,000	674,000
Interest income recognized	0	2,000
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	508,000		332,000
Troubled Debt Restructuring [Abstract]
Troubled Debt Restructurings Balance	293,000		236,000
Financing Receivable Modifications Performing Recorded Investment	0		0
Commercial and industrial loans \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	228,260,000		218,193,000
Commercial and industrial loans \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	3,689,000		4,647,000
Commercial and industrial loans \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	1,392,000		940,000
Commercial and industrial loans \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Consumer loans
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	52,000		331,000
60-89 days Past Due	254,000		10,000
90 Days or More Past Due	2,000		5,000
Total Past Due	308,000		346,000
Current	14,717,000		14,772,000
Total Loans Receivable	15,025,000		15,118,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	251,000		0
Unpaid Principal Balance	251,000		0
Specific Allowance	251,000		0
Loans without a specific allowance [Abstract]
Recorded Balance	42,000		15,000
Unpaid Principal Balance	361,000		60,000
Total Loans [Abstract]
Recorded Balance	293,000		15,000
Unpaid Principal Balance	612,000		60,000
Average recorded investment and interest income recognized [Abstract]
Average investment in impaired loans	294,000	34,000
Interest income recognized	1,000	0
Loans Receivable, Modifications, Still Accruing Interest	40,000	23,000
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	253,000		7,000
Troubled Debt Restructuring [Abstract]
Troubled Debt Restructurings Balance	40,000		9,000
Financing Receivable Modifications Performing Recorded Investment	40,000		9,000
Recorded Balance of Troubled Debt Restructurings [Abstract]
Financing Receivables, Modifications during Period, Number	2	0
Financing Receivables, Modifications during Period, Balance	32,000	0
Consumer loans \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	14,764,000		15,105,000
Consumer loans \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	8,000		9,000
Consumer loans \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	253,000		4,000
Consumer loans \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
All other loans
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	0		0
60-89 days Past Due	0		0
90 Days or More Past Due	0		0
Total Past Due	0		0
Current	8,718,000		8,736,000
Total Loans Receivable	8,718,000		8,736,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Specific Allowance	0		0
Loans without a specific allowance [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
Total Loans [Abstract]
Recorded Balance	0		0
Unpaid Principal Balance	0		0
All other loans \| Pass
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	8,718,000		8,736,000
All other loans \| Watch
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
All other loans \| Substandard
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
All other loans \| Doubtful
Loans Receivable Aging Analysis [Abstract]
Total Loans Receivable	0		0
Loans secured by real estate
Loans Receivable Aging Analysis [Abstract]
30-59 days Past Due	1,898,000		558,000
60-89 days Past Due	77,000		281,000
90 Days or More Past Due	1,285,000		1,330,000
Total Past Due	3,260,000		2,169,000
Current	736,837,000		744,305,000
Total Loans Receivable	740,097,000		746,474,000
Total Loans 90 days & Accruing	0		0
Loans with a specific allowance [Abstract]
Recorded Balance	1,092,000		1,324,000
Unpaid Principal Balance	1,657,000		4,080,000
Specific Allowance	181,000		179,000
Loans without a specific allowance [Abstract]
Recorded Balance	2,764,000		2,869,000
Unpaid Principal Balance	7,205,000		6,909,000
Total Loans [Abstract]
Recorded Balance	3,856,000		4,193,000
Unpaid Principal Balance	8,862,000		10,989,000
Average recorded investment and interest income recognized [Abstract]
Average investment in impaired loans	3,891,000	4,815,000
Interest income recognized	4,000	3,000
Balances of Nonaccrual Loans [Abstract]
Recorded balance of nonaccrual loans	3,407,000		3,766,000
Troubled Debt Restructuring [Abstract]
Troubled Debt Restructurings Balance	2,169,000		2,615,000
Financing Receivable Modifications Performing Recorded Investment	448,000		426,000
Recorded Balance of Troubled Debt Restructurings [Abstract]
Financing Receivables, Modifications during Period, Number	2	2
Financing Receivables, Modifications during Period, Balance	$ 34,000	$ 207,000

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings and are still accruing interest.

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Financing Receivables, Modifications during Period, Balance

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Financing Receivables, Modifications during Period, Number

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Loans and Leases Receivable, Including Held for Sale, Net of Deferred Income

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The allowance for loan losses related to financing receivables that have been modified by troubled debt restructurings.

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Amount of investment related to financing receivables modified by troubled debt restructurings that are still accruing interest.

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Minimum balance of loans for which credit quality analysis is performed.

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The number of days past due when the Company discontinues the accrual of interest income for the loan.

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No definition available.

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Minimum time period of satisfactory performance before returning a nonaccrual loan to accrual status.

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No definition available.

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Number of days past due under the modified terms, when a TDR is considered to be in payment default

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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- Definition

Financing receivables that are less than 60 days past due but more than 29 days past due.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

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- Definition

Financing receivables that are less than 90 days past due but more than 59 days past due.

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (d)

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Financing receivables that are current.

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Financing receivables that are equal to or greater than 90 days past due.

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of allowance for credit losses related to recorded investment.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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

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-Topic 310

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

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