Employee Benefit Plans - Additional Information (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) Director	Jun. 30, 2018 USD ($) Director	Jun. 30, 2019 USD ($) Hour Installment Director	Jun. 30, 2018 USD ($) Director	Dec. 31, 2018 USD ($)
401(k) Plan [Abstract]
Minimum age to participate			18 years
Minimum working hours to participate | Hour			20
Annual contribution per employee			100.00%
Employer matching contribution percentage on first 6% of deferred compensation			100.00%
Percent of employee's compensation deferred that receives company match			6.00%
Additional safe harbor contribution by employer, percent			3.00%
401(k) expenses	$ 181,000	$ 181,000	$ 411,000	$ 353,000
Deferred Compensation Plan [Abstract]
Number of directors participating in Deferred Compensation Plan | Director	0	0	0	0
Bank-owned life insurance	$ 90,000	$ 91,000	$ 183,000	$ 180,000
Accrued liability for deferred compensation program	125,000		125,000		$ 103,000
Former Key Employee [Member]
Deferred Compensation Plan [Abstract]
Deferred compensation expense	21,000	14,000	37,000	27,000
Bank-owned life insurance	7,300	7,200	14,000	14,000
Cash surrender value of life insurance policies	1,400,000		$ 1,400,000		1,400,000
Maximum [Member]
401(k) Plan [Abstract]
Employer matching contribution			6.00%
Deferred Compensation Plan [Abstract]
Number of installments for contributions | Installment			5
Minimum [Member]
Deferred Compensation Plan [Abstract]
Number of installments for contributions | Installment			1
Supplemental Executive Retirement Plan [Member]
Supplemental Executive Retirement Plan [Abstract]
Pension liability	2,800,000		$ 2,800,000		$ 2,700,000
Pension expense	$ 75,000	$ 73,000	$ 148,000	$ 146,000