Represents the amount of available-for-sale securities and loans that serve as collateral for borrowings.

No definition available.

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- Definition

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

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

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- Definition

Net increase or decrease in the carrying amount of the debt instrument for the period.

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-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
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- Definition

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

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- Definition

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.

+ References

No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

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

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- Definition

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

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- Definition

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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- Definition

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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Borrowed Funds (Narrative) (Details) - USD ($)		12 Months Ended
Borrowed Funds (Narrative) (Details) - USD ($)	Sep. 15, 2014	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Securities available-for-sale and loans pledged as collateral		$ 2,500,000,000	$ 2,400,000,000
Total available borrowing capacity from Federal Home Loan Bank		2,200,000,000
Qualifying collateral available for Federal Home Loan Bank borrowings		3,500,000,000
Outstanding at end of year		902,749,000	920,542,000
Accretion adjustment		(1,810,000)	(2,200,000)	$ (2,042,000)
Repurchase agreements
Debt Instrument [Line Items]
Decrease in agreement amount		(10,000,000.0)
Outstanding at end of year		42,700,000	52,700,000
Committed line of credit \| Line of credit
Debt Instrument [Line Items]
Borrowing capacity		12,000,000.0
Uncommitted lines of credit \| Line of credit
Debt Instrument [Line Items]
Borrowing capacity		475,000,000.0
Outstanding balance		18,000,000.0	0
Subordinated debenture maturing September 15, 2029
Debt Instrument [Line Items]
Outstanding at end of year		$ 74,026,000	73,926,000
Subordinated debenture maturing September 15, 2029 \| Interest rate period 1
Debt Instrument [Line Items]
Fixed interest rate		6.00%
Subordinated debenture maturing September 15, 2029 \| Interest rate period 2 \| LIBOR
Debt Instrument [Line Items]
Variable interest rate spread (as a percent)		3.315%
Subordinated debenture maturing September 15, 2029 \| Subordinated debentures and notes
Debt Instrument [Line Items]
Principal amount	$ 75,000,000.0
Accretion adjustment		$ 400,000	500,000
Capitalized financing costs		$ 1,000,000.0	$ 1,100,000
Subordinated debenture maturing September 15, 2029 \| Subordinated debentures and notes \| Interest rate period 1
Debt Instrument [Line Items]
Fixed interest rate	6.00%
Subordinated debenture maturing September 15, 2029 \| Subordinated debentures and notes \| Interest rate period 2 \| LIBOR
Debt Instrument [Line Items]
Variable interest rate spread (as a percent)	3.315%