Segment Reporting - Summary of Results for Reportable Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net interest income	$ 6,767	$ 7,257	$ 20,644	$ 21,758
Provision (reduction in reserve) for loan losses	(78)	(55)	(199)	95
Total non-interest income	996	1,180	3,355	3,812
Total non-interest expense	7,090	7,242	21,174	21,349
Income before income taxes	751	1,250	3,024	4,126
Provision for income taxes	207	413	870	1,297
Net income	544	837	2,154	2,829
Other significant items:
Total assets	548,537	562,741	548,537	562,741	$ 572,609
Total investment securities	239,009	215,870	239,009	215,870
Total loans, net	237,715	265,170	237,715	265,170	259,516
Investment in subsidiaries	5	5	5	5
Fixed asset additions	1,252	127	3,111	1,008
Depreciation and amortization expense	212	203	640	598
Total interest income from external customers	7,328	7,899	22,384	23,675
Eliminations [Member]
Segment Reporting Information [Line Items]
Total non-interest income	(840)	(1,095)	(3,153)	(3,720)
Total non-interest expense	(143)	(179)	(439)	(569)
Income before income taxes	(697)	(916)	(2,714)	(3,151)
Net income	(697)	(916)	(2,714)	(3,151)
Other significant items:
Total assets	(169,037)	(153,913)	(169,037)	(153,913)
Total loans, net	(72,785)	(60,095)	(72,785)	(60,095)
Investment in subsidiaries	(76,883)	(74,788)	(76,883)	(74,788)
Total interest income from affiliates	(1,003)	(821)	(2,808)	(2,389)
FUSB [Member]
Segment Reporting Information [Line Items]
Provision (reduction in reserve) for loan losses			(1,370)		(1,920)
Other significant items:
Total loans, net	156,935		156,935		187,500
FUSB [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net interest income	3,598	3,968	11,433	12,156
Provision (reduction in reserve) for loan losses	(400)	(550)	(1,370)	(1,050)
Total non-interest income	755	871	2,766	3,088
Total non-interest expense	4,443	4,726	13,110	13,823
Income before income taxes	310	663	2,459	2,471
Provision for income taxes	43	183	678	589
Net income	267	480	1,781	1,882
Other significant items:
Total assets	550,341	563,918	550,341	563,918
Total investment securities	238,929	215,790	238,929	215,790
Total loans, net	229,721	255,240	229,721	255,240
Investment in subsidiaries	5	5	5	5
Fixed asset additions	1,250	73	2,860	940
Depreciation and amortization expense	151	148	459	438
Total interest income from external customers	3,162	3,794	10,379	11,699
Total interest income from affiliates	1,000	818	2,801	2,382
ALC [Member]
Segment Reporting Information [Line Items]
Provision (reduction in reserve) for loan losses			1,171		1,846
Other significant items:
Total loans, net	80,780		80,780		$ 72,016
ALC [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net interest income	3,166	3,286	9,203	9,594
Provision (reduction in reserve) for loan losses	322	495	1,171	1,145
Total non-interest income	234	297	689	870
Total non-interest expense	2,430	2,490	7,400	7,489
Income before income taxes	648	598	1,321	1,830
Provision for income taxes	236	229	475	706
Net income	412	369	846	1,124
Other significant items:
Total assets	85,066	72,889	85,066	72,889
Total loans, net	80,779	70,025	80,779	70,025
Fixed asset additions	2	54	251	68
Depreciation and amortization expense	61	55	181	160
Total interest income from external customers	4,166	4,105	12,004	11,976
All Other [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net interest income	3	3	8	8
Total non-interest income	847	1,107	3,053	3,574
Total non-interest expense	360	205	1,103	606
Income before income taxes	490	905	1,958	2,976
Provision for income taxes	(72)	1	(283)	2
Net income	562	904	2,241	2,974
Other significant items:
Total assets	82,167	79,847	82,167	79,847
Total investment securities	80	80	80	80
Investment in subsidiaries	76,883	74,788	76,883	74,788
Total interest income from external customers			1
Total interest income from affiliates	$ 3	$ 3	$ 7	$ 7