Acquisitions (Schedule Of Supplemental Cash Flow Information Regarding Acquisitions) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental cash flow information regarding acquisitions
Assets acquired	$ 599	$ 284	$ 16
Liabilities assumed	(56)	(30)
Net assets acquired	542	254	16
Net cash paid	504	191	13
Seller financed debt	38	64	3
Purchase price	542	254	$ 16
Deferred tax liabilities	$ 21	$ 15

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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