Quarterly Results of Operations (Unaudited) - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2016	Sep. 30, 2016
Understatement of Net Income
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Quantifying misstatement in current year financial statements	$ 5
Overstatement of Net Income
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Quantifying misstatement in current year financial statements		$ 23

Amount of each individual error being corrected in the correcting adjustment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 1.N)
-URI http://asc.fasb.org/extlink&oid=26874127&loc=d3e30840-122693

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration