Allowance for Loan Losses - Allowance for Loan Losses by Portfolio Segment (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	$ 2,925	$ 3,094
(Charge-offs)	(392)	(1,028)
Recoveries	61	83
Provision	611us-gaap_ProvisionForLoanAndLeaseLosses	776us-gaap_ProvisionForLoanAndLeaseLosses
Ending Balance	3,205	2,925
Individually evaluated for impairment	676	667
Collectively evaluated for impairment	2,529	2,258
Mortgage Loans on Real Estate
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	2,465	2,572
(Charge-offs)	(313)	(879)
Recoveries	36	68
Provision	590	704
Ending Balance	2,778	2,465
Individually evaluated for impairment	665	634
Collectively evaluated for impairment	2,113	1,831
Commercial and Industrial loans
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	256	262
(Charge-offs)		(17)
Recoveries		1
Provision	67	10
Ending Balance	323	256
Collectively evaluated for impairment	323	256
Consumer and Other Loans
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	204	260
(Charge-offs)	(79)	(132)
Recoveries	25	14
Provision	(46)	62
Ending Balance	104	204
Individually evaluated for impairment	11	33
Collectively evaluated for impairment	$ 93	$ 171

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

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

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

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

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

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Amount of expense related to estimated loss from loan and lease transactions.

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