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Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | $ 0 |
Derivative Credit Risk Valuation Adjustment, Derivative Assets | 0 |
Derivative Credit Risk Valuation Adjustment, Derivative Liabilities | $ 0 |
Minimum |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Collateral discount | 15.00% | 15.00%
Maximum |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Collateral discount | 30.00% | 30.00%

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- Definition Unobservable Inputs Fair Value Measurement Collateral Discount Percent + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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- Definition Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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- Definition Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity. + References No definition available. + Details
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Period Type: | instant

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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. + Details
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- Definition Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
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- Details
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Balance Type: |
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- Details
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