Mergers, Acquisitions, and Dispositions ProForma Impact of Merger (Details) - USD ($) $ / shares in Thousands, $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Business Combination Proforma Non recurring Cost	$ 639	$ 116	$ 92
BusinessCombinationProformaIntercompanyRevenue	170	122	559
Business Acquisition, Pro Forma Revenue	8,556	10,062	33,823
Business Acquisition, Pro Forma Net Income (Loss)	$ 577	$ 800	$ 2,618
Business Acquisition, Pro Forma Earnings Per Share, Basic	$ 630	$ 870	$ 2,850
Business Acquisition, Pro Forma Earnings Per Share, Diluted	$ 620	$ 870	$ 2,840

BusinessCombinationProformaIntercompanyRevenue

No definition available.

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- Definition

Business Combination Proforma Non recurring Cost

+ References

No definition available.

+ Details

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

+ Details

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

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