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	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Allowance for loan losses:
Beginning balance	$ 6,168
Provision (reduction in reserve) for loan losses	(166)	414
Ending balance	5,401
Loan receivables:
Ending balance	253,015		274,317
Commercial and Industrial Loans [Member]
Loan receivables:
Ending balance	17,897		16,838
Consumer Loans [Member]
Loan receivables:
Ending balance	68,575		69,021
Other Loans [Member]
Loan receivables:
Ending balance	775		579
FUSB [Member]
Allowance for loan losses:
Beginning balance	3,486	6,272	6,272
Charge-offs	(128)		(1,941)
Recoveries	47		1,075
Provision (reduction in reserve) for loan losses	(525)		(1,920)
Ending balance	2,880		3,486
Ending balance individually evaluated for impairment	841		762
Ending balance collectively evaluated for impairment	2,039		2,724
Loan receivables:
Ending balance	171,485		191,175
Ending balance individually evaluated for impairment	9,429		10,605
Ending balance collectively evaluated for impairment	162,056		180,570
FUSB [Member] \| Commercial and Industrial Loans [Member]
Allowance for loan losses:
Beginning balance	141	592	592
Charge-offs			(289)
Recoveries	10		307
Provision (reduction in reserve) for loan losses	10		(469)
Ending balance	161		141
Ending balance collectively evaluated for impairment	161		141
Loan receivables:
Ending balance	17,897		16,838
Ending balance collectively evaluated for impairment	17,897		16,838
FUSB [Member] \| Commercial Real Estate [Member]
Allowance for loan losses:
Beginning balance	2,810	4,852	4,852
Charge-offs	(77)		(1,329)
Recoveries	4		587
Provision (reduction in reserve) for loan losses	(334)		(1,300)
Ending balance	2,403		2,810
Ending balance individually evaluated for impairment	841		762
Ending balance collectively evaluated for impairment	1,562		2,048
Loan receivables:
Ending balance	116,014		135,775
Ending balance individually evaluated for impairment	9,429		10,509
Ending balance collectively evaluated for impairment	106,585		125,266
FUSB [Member] \| Consumer Loans [Member]
Allowance for loan losses:
Beginning balance	114	180	180
Charge-offs	(11)		(147)
Recoveries	15		129
Provision (reduction in reserve) for loan losses	(52)		(48)
Ending balance	66		114
Ending balance collectively evaluated for impairment	66		114
Loan receivables:
Ending balance	7,254		7,188
Ending balance collectively evaluated for impairment	7,254		7,188
FUSB [Member] \| Residential Real Estate [Member]
Allowance for loan losses:
Beginning balance	421	635	635
Charge-offs	(40)		(176)
Recoveries	18		51
Provision (reduction in reserve) for loan losses	(149)		(89)
Ending balance	250		421
Ending balance collectively evaluated for impairment	250		421
Loan receivables:
Ending balance	29,545		30,795
Ending balance individually evaluated for impairment			96
Ending balance collectively evaluated for impairment	29,545		30,699
FUSB [Member] \| Other Loans [Member]
Allowance for loan losses:
Beginning balance		13	13
Recoveries			1
Provision (reduction in reserve) for loan losses			(14)
Loan receivables:
Ending balance	775		579
Ending balance collectively evaluated for impairment	775		579
ALC [Member]
Allowance for loan losses:
Beginning balance	2,682	3,124	3,124
Charge-offs	(735)		(3,089)
Recoveries	216		801
Provision (reduction in reserve) for loan losses	358		1,846
Ending balance	2,521		2,682
Ending balance collectively evaluated for impairment	2,521		2,682
Loan receivables:
Ending balance	81,530		83,142
Ending balance collectively evaluated for impairment	81,530		83,142
ALC [Member] \| Consumer Loans [Member]
Allowance for loan losses:
Beginning balance	2,336	2,667	2,667
Charge-offs	(655)		(2,778)
Recoveries	209		772
Provision (reduction in reserve) for loan losses	313		1,675
Ending balance	2,203		2,336
Ending balance collectively evaluated for impairment	2,203		2,336
Loan receivables:
Ending balance	61,321		61,833
Ending balance collectively evaluated for impairment	61,321		61,833
ALC [Member] \| Residential Real Estate [Member]
Allowance for loan losses:
Beginning balance	346	457	457
Charge-offs	(80)		(311)
Recoveries	7		29
Provision (reduction in reserve) for loan losses	45		171
Ending balance	318		346
Ending balance collectively evaluated for impairment	318		346
Loan receivables:
Ending balance	20,209		21,309
Ending balance collectively evaluated for impairment	20,209		21,309
FUSB & ALC [Member]
Allowance for loan losses:
Beginning balance	6,168	9,396	9,396
Charge-offs	(863)		(5,030)
Recoveries	263		1,876
Provision (reduction in reserve) for loan losses	(167)		(74)
Ending balance	5,401		6,168
Ending balance individually evaluated for impairment	841		762
Ending balance collectively evaluated for impairment	4,560		5,406
Loan receivables:
Ending balance	253,015		274,317
Ending balance individually evaluated for impairment	9,429		10,605
Ending balance collectively evaluated for impairment	243,586		263,712
FUSB & ALC [Member] \| Commercial and Industrial Loans [Member]
Allowance for loan losses:
Beginning balance	141	592	592
Charge-offs			(289)
Recoveries	10		307
Provision (reduction in reserve) for loan losses	10		(469)
Ending balance	161		141
Ending balance collectively evaluated for impairment	161		141
Loan receivables:
Ending balance	17,897		16,838
Ending balance collectively evaluated for impairment	17,897		16,838
FUSB & ALC [Member] \| Commercial Real Estate [Member]
Allowance for loan losses:
Beginning balance	2,810	4,852	4,852
Charge-offs	(77)		(1,329)
Recoveries	4		587
Provision (reduction in reserve) for loan losses	(334)		(1,300)
Ending balance	2,403		2,810
Ending balance individually evaluated for impairment	841		762
Ending balance collectively evaluated for impairment	1,562		2,048
Loan receivables:
Ending balance	116,014		135,775
Ending balance individually evaluated for impairment	9,429		10,509
Ending balance collectively evaluated for impairment	106,585		125,266
FUSB & ALC [Member] \| Consumer Loans [Member]
Allowance for loan losses:
Beginning balance	2,450	2,847	2,847
Charge-offs	(666)		(2,925)
Recoveries	224		901
Provision (reduction in reserve) for loan losses	261		1,627
Ending balance	2,269		2,450
Ending balance collectively evaluated for impairment	2,269		2,450
Loan receivables:
Ending balance	68,575		69,021
Ending balance collectively evaluated for impairment	68,575		69,021
FUSB & ALC [Member] \| Residential Real Estate [Member]
Allowance for loan losses:
Beginning balance	767	1,092	1,092
Charge-offs	(120)		(487)
Recoveries	25		80
Provision (reduction in reserve) for loan losses	(104)		82
Ending balance	568		767
Ending balance collectively evaluated for impairment	568		767
Loan receivables:
Ending balance	49,754		52,104
Ending balance individually evaluated for impairment			96
Ending balance collectively evaluated for impairment	49,754		52,008
FUSB & ALC [Member] \| Other Loans [Member]
Allowance for loan losses:
Beginning balance		13	13
Recoveries			1
Provision (reduction in reserve) for loan losses			(14)
Loan receivables:
Ending balance	775		579
Ending balance collectively evaluated for impairment	$ 775		$ 579

Provision reduction in reserve for loan losses.

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

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