Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) (USD $)	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Statement of Stockholders' Equity [Abstract]
Stock option exercises (shares)	329,825	395,425
Issuance of preferred stock (shares)	0	6,000,000
Purchase of treasury stock, shares	0	1,905,077
Cash dividends declared on preferred stock, per share	$ 0.34	$ 0
Cash dividends declared on common stock, per share	$ 0.50	$ 0.48

Aggregate dividends paid during the period for each share of common stock outstanding.

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Aggregate dividends declared during the period for each share of preferred stock outstanding.

+ References

No definition available.

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- Definition

Number of new stock issued during the period.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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

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-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 210.5-02.28,29)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

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

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