The amount authorized by an entity's Board of Directors under a stock repurchase plan.

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- Definition

The remaining repurchase amount authorized by an entity's Board of Directors under a stock repurchase plan.

+ Details

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- Definition

Number of shares that have been repurchased under the stock repurchase program.

+ Details

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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- Definition

Value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

+ References

+ Details

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- Definition

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

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 1

-Section B

-Paragraph 7

-Subparagraph b

+ Details

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Stock Repurchase Program (Details) (USD $) In Millions, except Share data	3 Months Ended	6 Months Ended		3 Months Ended	9 Months Ended
	Jun. 30, 2011	Jun. 30, 2011	Oct. 17, 2007	Sep. 30, 2011 Stock Repurchase Program Additional Authorization [Member]	Sep. 30, 2011 Stock Repurchase Program Additional Authorization [Member]	Feb. 22, 2011 Stock Repurchase Program Additional Authorization [Member]
Common stock repurchase authorized amount			$ 150.0			$ 100.0
Total stock repurchased, shares		6,422,587
Common stock repurchase price per share	$ 23.36			$ 24.02
Common stock repurchased and retired, shares				2,000,000
Common stock repurchased and retired, value				48.0
Treasury stock repurchase authorization amount available					$ 32.6