Leases - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) lease	Sep. 30, 2018 USD ($)	Aug. 20, 2019 USD ($)	Aug. 15, 2019 USD ($)	Feb. 28, 2019 USD ($)
Operating Lease, Weighted Average Remaining Lease Term	17 years 6 months 29 days		17 years 6 months 29 days
Operating Lease, Weighted Average Discount Rate, Percent	3.50%		3.50%
Operating Lease, Cost	$ 233,000	$ 251,000	$ 708,000	$ 744,000
Short-term Lease, Cost	0
Operating Lease, Payments	225,000
Lessee Operating lease Not Yet Commenced Operating Lease Right Of Use Asset					$ 100,000		$ 4,600,000
Number of first insurance offices leases | lease			7
Number of banking center locations leases | lease			5
Number of future banking location leases | lease			1
Number of loan production office leases | lease			1
Number of future loan production office leases | lease			1
Number of land leases | lease			2
Number of land leases used for parking | lease			1
Option extensions			true
February 2020
Lessee Operating lease Not Yet Commenced Operating Lease Right Of Use Asset						$ 1,100,000
April 2020
Lessee Operating lease Not Yet Commenced Operating Lease Right Of Use Asset						$ 1,800,000
Other Assets [Member]
Operating Lease, Right-of-Use Asset	8,300,000		$ 8,300,000
Other Liabilities [Member]
Operating Lease, Right-of-Use Asset	$ 8,900,000		$ 8,900,000
Minimum [Member]
Lessee, Operating Lease, Renewal Term	5 years		5 years
Maximum [Member]
Lessee, Operating Lease, Renewal Term	10 years		10 years