Long-Term Debt (Loss (gain) from Early Extinguishment of Debt Narrative) (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Loss (gain) from early extinguishment of debt		$ (64,000,000)	$ 31,000,000	$ (59,000,000)
Loss (gain) on extinguishment of debt, net of tax		$ (50,000,000)	$ 23,000,000	$ (46,000,000)
Maximum [Member]
Loss (gain) from early extinguishment of debt	$ 0

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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