Basis of Presentation Basis of Presentation (Out-of-period-correction) (Details) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Net cash provided by (used in) operating activities [Member]
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Net Cash Provided by (Used in) Operating Activities	$ 63
Net cash provided by (used in) investing activities [Member]
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Net Cash Provided by (Used in) Operating Activities	$ 63

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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