Hedges and Derivative Financial Instruments (Narrative) (Details)	12 Months Ended
Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 contract
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Number of interest rate derivatives held (in contract) \| contract	0	0
Derivative net hedge ineffectiveness	$ 0
Derivative instruments, loss reclassification from Accumulated OCI to income, estimated net amount to be transferred	$ 44,000,000

Amount of gain (loss) from the ineffectiveness of the hedge.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

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Number of interest rate derivative instruments held by the entity at the reporting date.

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