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

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- Definition

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

+ References

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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No definition available.

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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

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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

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

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-Section S99

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-Subparagraph (SX 210.3-04)

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Treasury Stock and Dividends - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended	9 Months Ended		46 Months Ended
	Aug. 13, 2014	Aug. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014
Equity [Abstract]
Treasury stock, shares acquired				136,874	105,000	486,874
Weighted average purchase price per share				$ 191.79	$ 187.61	$ 130.78
Total cost of treasury shares acquired				$ 26,300,000	$ 19,700,000	$ 63,700,000
Common stock remaining authorized for repurchase			213,126	213,126		213,126
Common stock dividend paid per share		$ 0.45
Total common stock cash dividend	$ 4,100,000	$ 4,100,000		$ 8,333,000
Cash dividends declared per share	$ 0.45		$ 0.45	$ 0.90
Dividend, record date				Oct. 31, 2014
Dividend, to be paid date				Nov. 14, 2014