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Organization Narrative shares in Millions, $ in Millions		3 Months Ended	6 Months Ended	12 Months Ended
	Jul. 31, 2014	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016 USD ($)	Feb. 07, 2017 USD ($) shares
Segment Reporting Information [Line Items]
Number of Reportable Segments			2
Subsequent Event, Date		Feb. 06, 2017
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	49.00%
Accelerated Share Repurchases, Settlement (Payment) or Receipt					$ 50
Accelerated Share Repurchases, Initial Shares | shares					2.9
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period				$ 15

X

- Definition

The initial number of shares transferred to the Company under an Accelerated Share Repurchase agreement, subject to final adjustment.

+ References

No definition available.

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X

- Definition

Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6405686&loc=d3e22802-112653

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X

- Definition

Total revenue reported by the acquired entity for its previous full fiscal year before the business acquisition.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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- Definition

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.

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- Definition

Date the event occurred after the balance sheet date but before financial statements are issues or available to be issued, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=52262685&loc=SL6759159-111685

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