Income Taxes Level 4 Capital Loss Carryover (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Capital Loss Carryforwards	$ 0	$ 78
Expiring Tax Year 2019 [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Capital Loss Carryforwards	0
Before Tax [Member]
Operating Loss Carryforwards [Line Items]
Tax Credit Carryforward, Amount	$ 0	$ 222

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 25
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=51675352&loc=d3e28680-109314

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant