Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Credit Risk Valuation Adjustment, Derivative Assets	$ 0	$ 0	$ 0
Derivative Credit Risk Valuation Adjustment, Derivative Liabilities	0	$ 0	$ 0
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	$ 0
Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateral discount	20.00%	20.00%	20.00%
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateral discount	30.00%	30.00%	30.00%

Unobservable Inputs Fair Value Measurement Collateral Discount Percent

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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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- 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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- 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 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

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