Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Share-Based Payments (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-Based Payment [Line Items]
Share-based payment arrangements Income tax benefits recognized	$ 172	$ 122	$ 175
Number of authorized shares of common stock for share-based payment arrangements (in shares)	109
Total unrecognized compensation cost related to nonvested share-based payment arrangements granted	$ 563
Weighted-average period to recognize the cost (years) - nonvested units	2 years 1 month 24 days
Total fair value of shares vested during the year - nonvested units	$ 450	327	336
Cash proceeds from exercise of stock options	$ 46	$ 43	$ 135
Performance Stock Units [Member]
Share-Based Payment [Line Items]
Vesting period	3 years
Restricted Stock Units \| Minimum Vesting Period [Member]
Share-Based Payment [Line Items]
Vesting period	2 years
Restricted Stock Units \| Minimum Vesting Period [Member] \| DIRECTV [Member]
Share-Based Payment [Line Items]
Vesting period	1 year
Restricted Stock Units \| Maximum Vesting Period [Member]
Share-Based Payment [Line Items]
Vesting period	10 years
Restricted Stock Units \| Maximum Vesting Period [Member] \| DIRECTV [Member]
Share-Based Payment [Line Items]
Vesting period	4 years
Other Nonvested Stock Units [Member]
Share-Based Payment [Line Items]
Vesting period	3 years