Fair Value Measurements (Narrative) (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateral discount	20.00%	20.00%
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateral discount	30.00%	30.00%

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.

No definition available.

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Balance Type:	na
Period Type:	duration