Subordinated Debentures And Notes (Details)	9 Months Ended
Sep. 30, 2019 USD ($) item	Mar. 05, 2015 USD ($)
Debt Instrument [Line Items]
Number of issuances of junior subordinated debentures \| item	2
Subordinated Note [Member]
Debt Instrument [Line Items]
Interest rate period, in years	5 years
Debt instrument, face amount		$ 9,750,000
Debt maturity date	Mar. 06, 2025
Subordinated Note [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Variable interest rate	5.75%
Subordinated Note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Variable interest rate	3.00%
Fixed Rate, First 5 Years [Member] \| Subordinated Note [Member]
Debt Instrument [Line Items]
Subordinate notes bearing fixed interest rate	4.25%
Prime Rate [Member] \| Subordinated Note [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
DNB Capital Trust I [Member]
Debt Instrument [Line Items]
Issuance date	Jul. 20, 2001
Floating rate capital preferred securities	$ 5,000,000
LIBOR rate, borrowing period, in months	6 months
Basis spread on variable rate	3.75%
Fixed interest rate	12.00%
Principal amount, floating rate junior subordinated debentures	$ 5,200,000
Maturity date range, start	Jul. 25, 2006
Maturity date range, end	Jul. 25, 2031
DNB Capital Trust II [Member]
Debt Instrument [Line Items]
Issuance date	Mar. 30, 2005
Floating rate capital preferred securities	$ 4,000,000
LIBOR rate, borrowing period, in months	3 months
Basis spread on variable rate	1.77%
Subordinate notes bearing fixed interest rate	6.56%
Interest rate period, in years	5 years
Principal amount, floating rate junior subordinated debentures	$ 4,100,000
Maturity date range, start	May 23, 2010
Maturity date range, end	May 23, 2035

Debt Instrument, Interest Rate Period, In Years

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- Definition

LIBOR rate, borrowing period

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- Definition

Number Of Issuances Of Junior Subordinated Debentures

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

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

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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

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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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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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- Definition

Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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- Definition

The noncurrent portion of the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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- Definition

The amount of capital contributed by the preferred partners.

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