Shareholders' Equity (Summary of Shares Outstanding) (Detail)	0 Months Ended	12 Months Ended
Jan. 28, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)		(138,646,382)us-gaap_CommonStockSharesOutstanding	(153,566,297)us-gaap_CommonStockSharesOutstanding	(151,888,780)us-gaap_CommonStockSharesOutstanding
Treasury Stock, Shares, Acquired	(10,825,227)us-gaap_TreasuryStockSharesAcquired		(10,825,227)us-gaap_TreasuryStockSharesAcquired
Purchases (in shares)		(3,813,191)	(5,745,529)	(1,000,000)
Issuances (in shares)		1,149,092	1,650,841	2,677,517
Ending balance (in shares)		(135,982,283)us-gaap_CommonStockSharesOutstanding	(138,646,382)us-gaap_CommonStockSharesOutstanding	(153,566,297)us-gaap_CommonStockSharesOutstanding
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)					(290,573,068)
Ending balance (in shares)		(290,573,068)	(290,573,068)	(290,573,068)	(290,573,068)
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)		(151,926,686)	(137,006,771)	(138,684,288)
Treasury Stock, Shares, Acquired			(10,825,227)
Purchases (in shares)		(3,813,191)	(5,745,529)	(1,000,000)
Issuances (in shares)		1,149,092	1,650,841	2,677,517
Ending balance (in shares)		(154,590,785)	(151,926,686)	(137,006,771)

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding.

+ References

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

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

+ References

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