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Amount of stock repurchase plan authorized.

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Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

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Amount remaining of a stock repurchase plan authorized.

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Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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Stock Plans - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cost of shares repurchased	$ 1,500,000,000	$ 1,891,000,000
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase value			7,700,000,000
Stock repurchase expiration date	Dec. 31, 2016
Number of shares repurchased	41.7
Average cost of shares repurchased	$ 35.98
Cost of shares repurchased	1,500,000,000
Stock repurchase remaining amount	$ 1,600,000,000