Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

No definition available.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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-Name Accounting Standards Codification
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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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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Recent Accounting Literature (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit	$ (2,749)	$ (2,741)	$ (2,752)
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact of adoption of new accounting principle	11
Cumulative-effect adjustment, Net of tax	11
Accumulated deficit		$ 11
Accounting Standards Update 2018-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact of adoption of new accounting principle	79
Accounting Standards Update 2018-11 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact of adoption of new accounting principle	$ 15