Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Apr. 17, 2019
Finite Lived Intangible Assets [Line Items]
Carrying value of goodwill	$ 31,206,000		$ 31,206,000		$ 412,000
Impairment of goodwill recognized			0		$ 0
Carrying value of intangible asset	3,519,000		$ 3,519,000
Mortgage Servicing Rights
Finite Lived Intangible Assets [Line Items]
Weighted average amortization period			6 years		7 years 6 months
Loans held for sale	384,000		$ 384,000		$ 0
Amount of mortgage loans sold and servicing rights retained			867,000		$ 1,600,000
Net gains recognized in gain on loans held for sale	15,000	$ 18,000	31,000	$ 45,000
Fair value of mortgage servicing rights portfolio	1,100,000	$ 1,000,000	1,100,000	$ 1,000,000
Optima Bank And Trust Company
Finite Lived Intangible Assets [Line Items]
Carrying value of goodwill	30,800,000		30,800,000			$ 30,794,000
Optima Bank And Trust Company | Core Deposit Intangibles
Finite Lived Intangible Assets [Line Items]
Intangible assets acquired	3,600,000
Amortization of intangible asset	90,000		90,000
Carrying value of intangible asset	$ 3,500,000		$ 3,500,000
Weighted average amortization period			10 years