FHLB Advances and Other Borrowings (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Term Loans	$ 25,000,000	$ 0
Line of credit, maximum borrowing capacity	15,000,000
Line of credit, outstanding balance	$ 0
Line of credit, unused capacity, commitment fee percentage	0.25%
Junior subordinated debt for Tier 1 capital purposes	$ 11,311,000	$ 11,060,000
LIBOR
Debt Instrument [Line Items]
Percentage over variable rate	1.75%
Parent Company
Debt Instrument [Line Items]
Term Loans	$ 25,000,000
Parent Company \| USB Cost of Funds
Debt Instrument [Line Items]
Percentage over variable rate	1.75%
Minimum
Debt Instrument [Line Items]
Interest rate on FHLB advances	1.54%	1.36%
Maximum
Debt Instrument [Line Items]
Interest rate on FHLB advances	7.22%	7.22%
Weighted Average
Debt Instrument [Line Items]
Interest rate on FHLB advances	1.75%	1.84%

Value of Junior Subordinated Debt For Tier One Capital Purposes.

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

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- Definition

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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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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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 fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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Including the current and noncurrent portions, carrying value at the balance sheet date of a financial instrument used to receive debt funding on a regular basis with original maturities ranging from 5-10 years.

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