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Risk Management Activities and Derivative Transactions Cash Flow from Hedging (Details) $ in Millions	Mar. 31, 2019 USD ($)
Cash Flow from Hedging [Abstract]
Associated bond issues currency exposure	$ 600

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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No definition available.

+ Details

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- Definition

Cash Flow from Hedging [Abstract]

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No definition available.

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