v3.19.1

Derivative Financial Instruments (Schedule of Derivative Offset Amounts) (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Derivative [Line Items] |  |  |
Energy commodity derivatives deposits |  | $ 23,820 | $ 0
Exchange Traded [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset |  | 597 | 62,166
Derivative Liability, Fair Value, Gross Liability |  | (13,869) | (7,155)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  |  | 55,011
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 13,272 |
Derivative, Collateral, Right to Reclaim Cash |  |  | (37,328)
Energy commodity derivatives deposits |  | 23,820 |
Amount After Offset | [1] | $ 10,548 | $ 17,683
[1] | Amount represents the maximum loss we would incur if all of our counterparties failed to perform on their derivative contracts.

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