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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Segment Information (Details) $ in Millions	3 Months Ended		9 Months Ended
Segment Information (Details) $ in Millions	Sep. 30, 2015 USD ($) state	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) state segment	Sep. 30, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			4
Merger-related expenses	$ 35	$ 0	$ 35	$ 0
Distribution Operations [Member]
Segment Reporting Information [Line Items]
Number of states in which entity operates \| state	7		7
Operating Segments [Member] \| Distribution Operations [Member]
Segment Reporting Information [Line Items]
Merger-related expenses	$ 0		$ 0
Operating Segments [Member] \| Other Segments [Member]
Segment Reporting Information [Line Items]
Merger-related expenses	$ 35		$ 35