Securities - Aggregate Amortized Costs and Fair Values of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 80,931	$ 83,804
Gross Unrealized Gains	554	118
Gross Unrealized (Losses)	(316)	(1,690)
Fair Value	81,169	82,232	[1]
US Government Agencies and Mortgage Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	51,941	51,126
Gross Unrealized Gains	205	35
Gross Unrealized (Losses)	(279)	(1,279)
Fair Value	51,867	49,882
State and Municipal Obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	16,810	20,484
Gross Unrealized Gains	281	60
Gross Unrealized (Losses)	(37)	(327)
Fair Value	17,054	20,217
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	12,180	12,194
Gross Unrealized Gains	68	23
Gross Unrealized (Losses)		(84)
Fair Value	$ 12,248	$ 12,133

[1] Derived from audited December 31, 2018 Consolidated Financial Statements.