Basis of Presentation, Uses of Estimates and Significant Accounting Policies Redeemable Noncontrolling Interests (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Noncontrolling Interest [Line Items]
Redeemable noncontrolling interest, beginning of period	$ 1,908
Acquisitions	87	$ 521	$ 2,112
Redemptions			283
Distributions	(279)	(228)	(152)
Fair value and other adjustments	316	163	(113)
Redeemable Noncontrolling Interest, end of period	1,726	1,908
Redeemable Noncontrolling Interests [Member]
Noncontrolling Interest [Line Items]
Redeemable noncontrolling interest, beginning of period	1,908	2,189
Net earnings	115	123
Acquisitions	90	102
Redemptions	(618)	(90)
Distributions	(69)	(53)
Fair value and other adjustments	300	(363)
Redeemable Noncontrolling Interest, end of period	$ 1,726	$ 1,908	$ 2,189

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

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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

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Amount of increase in noncontrolling interest from a business combination.

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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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