Other Borrowings and Notes Payable (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Feb. 23, 2016
Debt Instrument [Line Items]
Loans Payable	$ 34,286,000
Line of Credit, Current			$ 25,000,000
Securities sold under agreement to repurchase	230,886,000	$ 221,450,000
Total	230,886,000	221,450,000
Amount withdrawn	0	2,000,000
Unsecured term loan, face amount	40,000,000.0
Other Borrowings
Debt Instrument [Line Items]
Maximum balance outstanding at any month-end	230,886,000	231,450,000
Average balance during the year	$ 169,179,000	$ 170,963,000
Average interest rate during the year	0.69%	0.41%
Average interest rate at December 31	0.91%	0.49%
Line of Credit
Debt Instrument [Line Items]
Maximum balance outstanding at any month-end	$ 2,000,000	$ 2,000,000
Average balance during the year	$ 323,000	$ 22,000
Average interest rate during the year	4.61%	4.63%
Average interest rate at December 31	0.00%	4.63%
Remaining borrowing capacity	$ 1,100,000,000
Aggregate of pledge secured by certain eligible loans	1,300,000,000
Amount withdrawn	0
Unsecured Term Loan
Debt Instrument [Line Items]
Maximum balance outstanding at any month-end	40,000,000
Average balance during the year	$ 30,810,000
Average interest rate during the year	3.55%
Average interest rate at December 31	3.00%

Short-term and Long-term Debt, Average Outstanding Amount

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Short-term and Long-term Debt, Maximum Month-end Outstanding Amount

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Face (par) amount of debt instrument at time of issuance.

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The average effective interest rate during the reporting period.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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