Represents the operating margin assigned to segments for the period.

No definition available.

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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.

+ References

No definition available.

+ Details

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- Definition

Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

+ References

No definition available.

+ Details

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ 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 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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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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- Details

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- Details

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- Details

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Segment Information (Details) $ in Millions	3 Months Ended								12 Months Ended
Segment Information (Details) $ in Millions	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) segment	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Segment Reporting Information [Line Items]
Operating revenues	$ 4,476	$ 4,554	$ 4,419	$ 4,451	$ 4,438	$ 4,514	$ 4,541	$ 4,538	$ 17,900	$ 18,031	$ 18,095
Expenses									15,295	15,621	16,642
OPERATING INCOME	$ 751	$ 656	$ 549	$ 649	$ 483	$ 619	$ 655	$ 653	$ 2,605	2,410	1,453
Number of reportable segments (segments) \| segment									2
Operating segments (segments)
Segment Reporting Information [Line Items]
Operating revenues									$ 16,668	17,028	17,095
Expenses									8,459	8,509	8,167
OPERATING INCOME									$ 8,209	$ 8,519	$ 8,928
Margin percentage (percent)									49.00%	50.00%	52.00%
Business
Segment Reporting Information [Line Items]
Operating revenues									$ 10,647	$ 11,034	$ 11,091
Expenses									6,034	6,089	5,808
OPERATING INCOME									$ 4,613	$ 4,945	$ 5,283
Margin percentage (percent)									43.00%	45.00%	48.00%
Consumer
Segment Reporting Information [Line Items]
Operating revenues									$ 6,021	$ 5,994	$ 6,004
Expenses									2,425	2,420	2,359
OPERATING INCOME									$ 3,596	$ 3,574	$ 3,645
Margin percentage (percent)									60.00%	60.00%	61.00%