Redeemable Noncontrolling Interests (Changes in Redeemable Noncontrolling Interests) (Details) - USD ($) $ in Millions	12 Months Ended	34 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2018
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance at beginning of period	$ 118
Net purchase of redeemable noncontrolling interests	(19)	$ (1)	$ 7	$ (103)
Balance at end of period	12	118		12
naviHealth [Member]
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance at beginning of period	118	117
Net earnings attributable to redeemable noncontrolling interest	2	4
Net purchase of redeemable noncontrolling interests	(103)	(3)
Noncontrolling Interest, Change in Redemption Value	(5)
Balance at end of period	$ 12	$ 118	$ 117	$ 12

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

+ References

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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- Definition

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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