New Accounting Standards New Accounting Standards (Details) - USD ($) $ in Millions	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ (19,311)	$ (18,976)	$ (19,225)	$ (18,979)	$ (18,910)	$ (18,996)
Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			8
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ (19,293)	$ (19,026)		$ (18,497)	$ (18,553)	$ (18,527)
Retained Earnings [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			$ 8