Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount of advances from the Federal Home Loan Bank (FHLB).

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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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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

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Borrowings - Narrative (Details) - USD ($)	Jul. 26, 2016	Aug. 05, 2014	Dec. 31, 2020	Feb. 26, 2020	Dec. 31, 2019
Line of Credit Facility [Line Items]
Long-term line of credit			$ 107,683,000		$ 86,426,000
Proceeds from issuance of subordinated long-term debt	$ 147,400,000	$ 68,800,000
Subordinated Notes
Line of Credit Facility [Line Items]
Interest rate, stated percentage	5.00%	5.75%	5.42%		5.42%
Face amount	$ 150,000,000.0	$ 70,000,000.0
Payments of debt issuance costs	$ 2,600,000	$ 1,200,000
Federal Home Loan Bank – current portion
Line of Credit Facility [Line Items]
Interest rate, stated percentage				1.81%
Long-term debt				$ 50,000,000
Maximum
Line of Credit Facility [Line Items]
Federal Home Loan Bank, advances, branch of FHLB bank, amount of advances			$ 1,600,000,000
C D A R S
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity			1,500,000,000
Long-term line of credit			682,000
I N D
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity			1,500,000,000
Long-term line of credit			1,300,000,000
Loan Agreement and Related Stock Security Agreement
Line of Credit Facility [Line Items]
Long-term line of credit			350,000,000
Federal Reserve Bank of Richmond
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity			644,600,000
Federal Funds
Line of Credit Facility [Line Items]
Debt instrument, unused borrowing capacity, amount			$ 170,000,000