Acquisitions (Schedule Of Acqusition And Integration Costs) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Integration costs	$ 25	$ 413
Total acquisition and integration costs	25	436
CTF Acquisition [Member]
Business Acquisition [Line Items]
Acquisition costs		23
Integration costs	$ 25	412
Connecticut Acquisition [Member]
Business Acquisition [Line Items]
Integration costs		$ 1

Acquisition-related costs and integration costs incurred to effect a business combination which costs have been expensed during the period. Acquisition costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees. Integration costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

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- Definition

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

+ References

No definition available.

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- Details

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- Details

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