Long-Term Investments (Schedule Of Pre-Tax Income And Income Tax Effects Related To Investments In Leveraged Leases) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Long-term Investments [Abstract]
Pre-Tax Income (Loss) from Leases	$ (135)	$ 12	$ 24
Income Tax Expense (Benefit) on Income from Leases	$ (51)	$ 5	$ 32

The tax effect from the current year income from arrangements meeting the criteria for classification as a leveraged lease.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=7662751&loc=d3e45152-112736

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration