Securities Available for Sale - Schedule of Amortized Cost and Fair Value of Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 69,335	$ 61,381
Gross Unrealized Gains	671	1,198
Gross Unrealized Losses	(1,369)	(312)
Fair Value	68,637	62,267
Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	68,790	60,836
Gross Unrealized Gains	671	1,198
Gross Unrealized Losses	(1,362)	(312)
Fair Value	68,099	61,722
Debt Securities [Member] \| US Government-sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,999	6,886
Gross Unrealized Gains	92	159
Gross Unrealized Losses	(10)	(12)
Fair Value	4,081	7,033
Debt Securities [Member] \| Corporate [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,044	4,250
Gross Unrealized Gains	54	78
Gross Unrealized Losses	(18)	(48)
Fair Value	3,080	4,280
Debt Securities [Member] \| Municipal [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	13,857	15,327
Gross Unrealized Gains	254	472
Gross Unrealized Losses	(56)	(24)
Fair Value	14,055	15,775
Debt Securities [Member] \| Residential Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21,130	14,277
Gross Unrealized Gains	172	352
Gross Unrealized Losses	(580)	(120)
Fair Value	20,722	14,509
Debt Securities [Member] \| Commercial Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	14,676	5,465
Gross Unrealized Gains	56	87
Gross Unrealized Losses	(554)	(108)
Fair Value	14,178	5,444
Debt Securities [Member] \| Commercial Mortgage Backed Securities, U.S. Government-guaranteed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	9,589	11,742
Gross Unrealized Gains	12	26
Gross Unrealized Losses	(144)
Fair Value	9,457	11,768
Debt Securities [Member] \| Collateralized Mortgage Obligations, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,127	2,437
Gross Unrealized Gains	28	18
Fair Value	2,155	2,455
Debt Securities [Member] \| Collateralized Mortgage Obligations, US Government Guaranteed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	368	452
Gross Unrealized Gains	3	6
Fair Value	371	458
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	545	545
Gross Unrealized Losses	(7)
Fair Value	$ 538	$ 545

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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