Loans and Allowance for Loan Losses - Schedule of Changes in Allowance for Loan Losses and Recorded Investment in Loans (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Allowance for loan losses:
Ending balance	$ 6,168	$ 9,396
Loan receivables:
Ending balance	274,317	315,433
Other Loans [Member]
Loan receivables:
Ending balance	579	604
FUSB & ALC [Member]
Allowance for loan losses:
Beginning balance	9,396	19,278
Charge-offs	(5,030)	(13,131)
Recoveries	1,876	3,891
Provision	(74)	(642)
Ending balance	6,168	9,396
Ending balance individually evaluated for impairment	762	3,069
Ending balance collectively evaluated for impairment	5,406	6,327
Loan receivables:
Ending balance	274,317	315,433
Ending balance individually evaluated for impairment	10,605	32,551
Ending balance collectively evaluated for impairment	263,712	282,882
FUSB & ALC [Member] \| Commercial [Member]
Allowance for loan losses:
Beginning balance	592	977
Charge-offs	(289)	(537)
Recoveries	307	141
Provision	(469)	11
Ending balance	141	592
Ending balance individually evaluated for impairment		219
Ending balance collectively evaluated for impairment	141	373
Loan receivables:
Ending balance	16,838	37,772
Ending balance individually evaluated for impairment		753
Ending balance collectively evaluated for impairment	16,838	37,019
FUSB & ALC [Member] \| Commercial Real Estate [Member]
Allowance for loan losses:
Beginning balance	4,852	14,216
Charge-offs	(1,329)	(8,055)
Recoveries	587	2,747
Provision	(1,300)	(4,056)
Ending balance	2,810	4,852
Ending balance individually evaluated for impairment	762	2,839
Ending balance collectively evaluated for impairment	2,048	2,013
Loan receivables:
Ending balance	135,775	156,634
Ending balance individually evaluated for impairment	10,509	28,813
Ending balance collectively evaluated for impairment	125,266	127,821
FUSB & ALC [Member] \| Consumer [Member]
Allowance for loan losses:
Beginning balance	2,847	2,901
Charge-offs	(2,925)	(3,329)
Recoveries	901	970
Provision	1,627	2,305
Ending balance	2,450	2,847
Ending balance collectively evaluated for impairment	2,450	2,847
Loan receivables:
Ending balance	69,021	58,824
Ending balance collectively evaluated for impairment	69,021	58,824
FUSB & ALC [Member] \| Residential Real Estate [Member]
Allowance for loan losses:
Beginning balance	1,092	1,118
Charge-offs	(487)	(1,210)
Recoveries	80	29
Provision	(82)	1,155
Ending balance	767	1,092
Ending balance individually evaluated for impairment		11
Ending balance collectively evaluated for impairment	767	1,081
Loan receivables:
Ending balance	52,104	61,599
Ending balance individually evaluated for impairment	96	2,985
Ending balance collectively evaluated for impairment	52,008	58,614
FUSB & ALC [Member] \| Other Loans [Member]
Allowance for loan losses:
Beginning balance	13	66
Recoveries	1	4
Provision	(14)	(57)
Ending balance		13
Ending balance collectively evaluated for impairment		13
Loan receivables:
Ending balance	579	604
Ending balance collectively evaluated for impairment	579	604
ALC [Member]
Allowance for loan losses:
Beginning balance	3,124	3,513
Charge-offs	(3,089)	(3,504)
Recoveries	801	895
Provision	1,846	2,220
Ending balance	2,682	3,124
Ending balance collectively evaluated for impairment	2,682	3,124
Loan receivables:
Ending balance	83,142	75,559
Ending balance collectively evaluated for impairment	83,142	75,559
ALC [Member] \| Consumer [Member]
Allowance for loan losses:
Beginning balance	2,667	2,733
Charge-offs	(2,778)	(2,979)
Recoveries	772	874
Provision	1,675	2,039
Ending balance	2,336	2,667
Ending balance collectively evaluated for impairment	2,336	2,667
Loan receivables:
Ending balance	61,833	48,938
Ending balance collectively evaluated for impairment	61,833	48,938
ALC [Member] \| Residential Real Estate [Member]
Allowance for loan losses:
Beginning balance	457	780
Charge-offs	(311)	(525)
Recoveries	29	21
Provision	171	181
Ending balance	346	457
Ending balance collectively evaluated for impairment	346	457
Loan receivables:
Ending balance	21,309	26,621
Ending balance collectively evaluated for impairment	21,309	26,621
FUSB [Member]
Allowance for loan losses:
Beginning balance	6,272	15,765
Charge-offs	(1,941)	(9,627)
Recoveries	1,075	2,996
Provision	(1,920)	(2,862)
Ending balance	3,486	6,272
Ending balance individually evaluated for impairment	762	3,069
Ending balance collectively evaluated for impairment	2,724	3,203
Loan receivables:
Ending balance	191,175	239,874
Ending balance individually evaluated for impairment	10,605	32,551
Ending balance collectively evaluated for impairment	180,570	207,323
FUSB [Member] \| Commercial [Member]
Allowance for loan losses:
Beginning balance	592	977
Charge-offs	(289)	(537)
Recoveries	307	141
Provision	(469)	11
Ending balance	141	592
Ending balance individually evaluated for impairment		219
Ending balance collectively evaluated for impairment	141	373
Loan receivables:
Ending balance	16,838	37,772
Ending balance individually evaluated for impairment		753
Ending balance collectively evaluated for impairment	16,838	37,019
FUSB [Member] \| Commercial Real Estate [Member]
Allowance for loan losses:
Beginning balance	4,852	14,216
Charge-offs	(1,329)	(8,055)
Recoveries	587	2,747
Provision	(1,300)	(4,056)
Ending balance	2,810	4,852
Ending balance individually evaluated for impairment	762	2,839
Ending balance collectively evaluated for impairment	2,048	2,013
Loan receivables:
Ending balance	135,775	156,634
Ending balance individually evaluated for impairment	10,509	28,813
Ending balance collectively evaluated for impairment	125,266	127,821
FUSB [Member] \| Consumer [Member]
Allowance for loan losses:
Beginning balance	180	168
Charge-offs	(147)	(350)
Recoveries	129	96
Provision	(48)	266
Ending balance	114	180
Ending balance collectively evaluated for impairment	114	180
Loan receivables:
Ending balance	7,188	9,886
Ending balance collectively evaluated for impairment	7,188	9,886
FUSB [Member] \| Residential Real Estate [Member]
Allowance for loan losses:
Beginning balance	635	338
Charge-offs	(176)	(685)
Recoveries	51	8
Provision	(89)	974
Ending balance	421	635
Ending balance individually evaluated for impairment		11
Ending balance collectively evaluated for impairment	421	624
Loan receivables:
Ending balance	30,795	34,978
Ending balance individually evaluated for impairment	96	2,985
Ending balance collectively evaluated for impairment	30,699	31,993
FUSB [Member] \| Other Loans [Member]
Allowance for loan losses:
Beginning balance	13	66
Recoveries	1	4
Provision	(14)	(57)
Ending balance		13
Ending balance collectively evaluated for impairment		13
Loan receivables:
Ending balance	579	604
Ending balance collectively evaluated for impairment	$ 579	$ 604

Amount of direct write-downs of accounts receivable charged against the allowance.

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

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-Name Accounting Standards Codification

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Amount of increase (decrease) of allowance reserve for credit loss.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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