Amount of drawings outstanding on short-term borrowings.

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Federal home loan bank advances penalties.

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Federal home loan bank advances prepayment

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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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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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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 balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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The portion of the carrying amount of short-term borrowings outstanding as of the balance sheet date which accrues interest at a set, unchanging rate.

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No definition available.

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Description of the short-term debt arrangement, and disclosures pertaining to the underlying arrangements, including repayment terms, interest rates, restrictions on assets and activities, debt covenants, and other matters important to users of the financial statements.

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Debt (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
Debt (Narrative) (Details) - USD ($)	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Debt Instrument [Line Items]
Maturity of federal funds purchased from correspondent banks			one business day
Real estate secured loans	$ 1,220,316,000		$ 1,220,316,000
Current borrowing available	471,029,000		471,029,000
Maximum borrowing capacity	851,213,000		851,213,000
Short term borrowings	203,842,000		203,842,000
Long-term debt outstanding	75,199,000		75,199,000		$ 32,903,000
FHLB prepayment	22,500,000		22,500,000
FHLB prepayment penalties	26,000	$ 0	165,000	$ 0
FHLB [Member]
Debt Instrument [Line Items]
Letter of credit outstanding, amount	306,551,000		306,551,000		169,051,000
Paycheck Protection Program Liquidity Facility [Member]
Debt Instrument [Line Items]
Short term borrowings	$ 203,842,000		$ 203,842,000		0
Short-term borrowings, term			five years
Short-term borrowings, interest Rate	0.35%		0.35%
Other Correspondent Banks [Member]
Debt Instrument [Line Items]
Outstanding drawings			$ 0		0
Line of credit facility, remaining borrowing capacity	$ 35,000,000		35,000,000
Short term borrowings	$ 0		0		0
FHLB Short-Term Borrowings [Member]
Debt Instrument [Line Items]
Outstanding drawings			$ 0		$ 0