Nature of Operations and Summary of Significant Accounting Policies (Details Textual)	3 Months Ended
	Mar. 31, 2020 USD ($) quarter numberOfComponents operating_segment division	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Number of Bank Divisions | division	16
Number of Operating Segments | operating_segment	1
Forecasting period used to determine ACL | quarter	4
Number of components used in methodology in determining ACL | numberOfComponents	2
Period of Finance Receivable Modifications Due to COVID-19	6 months
Maximum Term Leases Will Be Considered Short-term	12 months
Revenue from Contracts with Customers	$ 14,458,000	$ 18,446,000
Impairment losses on receivables related to contracts with customers	0		$ 0
Cumulative Effect of New Accounting Principle in Period of Adoption	(12,347,000)	(25,458,000)
Allowance for credit losses on loans	150,190,000	129,786,000	124,490,000	$ 131,239,000
Deferred tax asset	0		$ 2,037,000
Retained Earnings Substantially Restricted
Cumulative Effect of New Accounting Principle in Period of Adoption	(12,347,000)	$ (25,458,000)
Accounting Standards Update 2016-13
Allowance for credit losses on loans	3,720,000
ACL on off-balance sheet credit exposures	12,817,000
Deferred tax asset	4,190,000
Accounting Standards Update 2016-13 | Retained Earnings Substantially Restricted
Cumulative Effect of New Accounting Principle in Period of Adoption	$ (12,347,000)
Minimum Range
Period Past Due to Consider Loan as Delinquent	30 days
Period Past Due to Consider Loan as Non Accrual	90 days
Period Past Due to Consider Loan as Purchased Credit-deteriorated Loan	90 days
Number of Days Delinquent to Charge off Loans	120 days
Number of years for home equity loan origination term	10 years
Maximum Range
Period Past Due to Consider Loan as Delinquent	89 days
Number of years for home equity loan origination term	15 years