Stock repurchase program additional authorized amount.

No definition available.

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- Definition

Stock repurchase program extended expiration date.

+ References

No definition available.

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- Definition

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

+ References

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-Name Accounting Standards Codification
-Topic 505
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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 format.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

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

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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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- Definition

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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Shareholders' Equity (Narrative) (Details) - USD ($)			1 Months Ended							3 Months Ended		9 Months Ended		50 Months Ended
Shareholders' Equity (Narrative) (Details) - USD ($)	Oct. 30, 2017	Jul. 29, 2016	Nov. 30, 2020	Aug. 31, 2020	Jul. 31, 2020	May 31, 2020	Apr. 30, 2020	Mar. 31, 2020	Feb. 29, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Jul. 28, 2020	Jul. 27, 2020	Jul. 31, 2018
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, repurchased cost											$ 33,100,000	$ 34,400,000	$ 81,200,000
Quarterly dividends declared					$ 0.20		$ 0.20		$ 0.20
Dividends declared				$ 0.20		$ 0.20		$ 0.20		$ 0.20	$ 0.175	$ 0.60	$ 0.525
Dividends payable, date to be paid, year and month				2020-08		2020-05		2020-03
Forecast [Member]
Equity Class Of Treasury Stock [Line Items]
Dividends declared			$ 0.21
Dividends payable, date to be paid, year and month			2020-11
Common Stock
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, expiration date		Jul. 31, 2018
Stock repurchase program, additional authorized amount	$ 250,000,000.0														$ 500,000,000.0		$ 300,000,000.0
Shares repurchase program, extended expiration date	Oct. 31, 2020
Stock repurchase program, remaining authorized repurchase amount										$ 603,800,000		$ 603,800,000		$ 603,800,000
Shares repurchase program, shares repurchased											347,304	382,170	994,995
Common Stock \| Share Repurchase Program Excluding Accelerated Share Repurchase
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, shares repurchased												400,000
Shares repurchase program, repurchased cost												$ 34,400,000
Shares repurchase program, average price per share												$ 89.99
Common Stock \| Share Repurchase Program Including Accelerated Share Repurchase
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, shares repurchased														9,600,000
Shares repurchase program, repurchased cost														$ 596,200,000
Shares repurchase program, average price per share														$ 62.13
Common Stock \| Maximum [Member]
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, authorized amount		$ 150,000,000.0														$ 1,200,000,000.0	$ 700,000,000.0