v3.20.1

Derivative Financial Instruments (Schedule of Derivative Offset Amounts) (Details) - Exchange Traded [Member] - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Derivative [Line Items] |  |
Derivative Liability, Fair Value, Gross Liability | $ (11,033) | $ (7,155)
Derivative Asset, Fair Value, Gross Asset | 811 | 62,166
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | 55,011
Derivative Asset, Fair Value, Amount Offset Against Collateral | (10,222) |
Derivative, Collateral, Right to Reclaim Cash | 27,415 |
Derivative, Collateral, Obligation to Return Cash |  | (37,328)
Amount After Offset | $ 17,193 | $ 17,683

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