Commitment and Contingenices (Narrative) (Details) - USD ($)	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Loss Contingencies
Contingent Residual Support Agreement, Amount	$ 2,000,000,000
Estimated litigation liability	21,000,000	$ 22,000,000
Attorney General of Commonwealth [Member]
Loss Contingencies
Legal Fees	$ 19,000,000
Percentage Of Recovery	50.00%
Reimbursement expert and consultant cost, maximum	$ 150,000

Amount of senior notes of an affiliate, the Partnership has agreed to provide contingent residual support for.

No definition available.

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- Definition

Potential portion of refund to customers in connection with a regulatory complaint.

+ References

No definition available.

+ Details

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- Definition

Maximum amount of costs to be reimbursed by the company in connection with a regulatory complaint.

+ References

No definition available.

+ Details

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- Definition

The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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