Related Party Transactions and Former Parent Company Investment - Narrative (Details) - USD ($) $ in Millions		3 Months Ended	9 Months Ended
Jan. 31, 2017	Sep. 30, 2016	Sep. 30, 2016
Related Party Transaction [Line Items]
Related party payment at separation	$ 161
Corporate Cost Allocations		$ 41	$ 125

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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Balance Type:	na
Period Type:	duration