Other Real Estate Owned, Net - Carrying Values of Properties Included in Other Real Estate Owned (OREO) (Detail) $ in Thousands	Mar. 31, 2019 USD ($) Property	Dec. 31, 2018 USD ($) Property
Real Estate Properties [Line Items]
No. of Properties | Property	26	26
Carrying Value | $	$ 3,718	$ 3,597	[1]
Residential
Real Estate Properties [Line Items]
No. of Properties | Property	7	6
Carrying Value | $	$ 1,477	$ 1,339
Land
Real Estate Properties [Line Items]
No. of Properties | Property	16	17
Carrying Value | $	$ 1,724	$ 1,741
Commercial properties
Real Estate Properties [Line Items]
No. of Properties | Property	3	3
Carrying Value | $	$ 517	$ 517

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