Income Taxes (Operating Loss Carryforwards Narrative) (Details) - State and Local Jurisdiction [Member] $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($)
Operating Loss Carryforwards [Line Items]
Net operating loss and credit carryforwards	$ 5,700
Operating Loss Carryforwards, Valuation Allowance	$ 6
Minimum [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards, Expiration Date	Jan. 01, 2016
Maximum [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards, Expiration Date	Jan. 01, 2035

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

+ References

+ Details

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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.

+ References

No definition available.

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- Definition

The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 30
-Paragraph 5
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=6907311&loc=d3e30536-109315

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

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