Accounting Policies - Additional Information (Details) - USD ($)			3 Months Ended		9 Months Ended
	Mar. 06, 2020	Jan. 01, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Jul. 16, 2019
Schedule Of Accounting Policies [Line Items]
Number of shares authorized to be repurchased								2,250,000
Number of shares repurchased	1,000,000				373,323
Average price per share repurchased	$ 15.19				$ 15.86
Shares, non-dilutive (in shares)			492,273	340,540	273,776
Impact of adoption of ASU No. 2016-13							$ 15,635,000
Initial PCD allowance		$ 2,800,000			$ 2,786,000
Accrued interest receivable			$ 13,400,000		$ 13,400,000
Loan delinquency period					90 days
Minimum period required for satisfactory performance to return loan from non-accrual to accrual status					6 months
Period of loan sold by mortgage company					30 days
Minimum period seldom held					90 days
Mortgage loan deferred due cost					$ 0
Mortgage warehousing maximum pay off period					30 days
Reclassifications effect on net income						$ 0
Retained Earnings
Schedule Of Accounting Policies [Line Items]
Impact of adoption of ASU No. 2016-13							15,635,000
Minimum
Schedule Of Accounting Policies [Line Items]
Loan delinquency period					90 days
Delay or shortfall in payments of loan					30 days
Maximum
Schedule Of Accounting Policies [Line Items]
Allowance for loan losses charge down family first and junior lien mortgages past due period					180 days
Allowance for loan losses charge down unsecured open end loans past due period					90 days
Allowance for loan losses charge down other secured loans past due period					90 days
Accounting Standards Update 2016-13 | Retained Earnings
Schedule Of Accounting Policies [Line Items]
Impact of adoption of ASU No. 2016-13							$ 15,600,000