Compensation Expense [Abstract]

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- Definition

Disclosure of the aggregate tax benefit realized from the issuance of stock and settlement of RPSRs and RSRs.

+ References

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- Definition

Unrecognized Compensation Expense [Abstract]

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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-Publisher FASB
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-SubTopic 10
-Section 50
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Stock Compensation Plans Compensation and Unrecognized Compensation Expense (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Compensation Expense [Abstract]
Share-based Payment Arrangement, Expense	$ 3.0	$ 7.0	$ 16.0	$ 19.0
Tax benefits for stock-based compensation	1.0	1.0	3.0	3.0
Stock Awards [Member]
Compensation Expense [Abstract]
Employee Service Share-Based Compensation, Tax Benefit Realized From Issuance Of Instruments Other Than Options			$ 3.0	$ 5.0
Restricted Stock [Member]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation expense, period for recognition			1 year
Restricted performance stock rights
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation expense	34.0		$ 34.0
Unrecognized compensation expense, period for recognition			1 year 4 months 24 days
Maximum \| Stock Awards [Member]
Compensation Expense [Abstract]
Employee Service Share-Based Compensation, Tax Benefit Realized From Issuance Of Instruments Other Than Options	1.0	$ 1.0
Maximum \| Restricted Stock [Member]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation expense	$ 1.0		$ 1.0