Stock-Based Compensation (Number Of Shares And Related Grant Date Fair Value Of PSU) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date per share fair value (in dollars per share)	$ 24.26
Risk-free interest rate	2.80%	2.30%	2.30%
Expected life in years	7 years 9 months 18 days	6 years	6 years
Expected volatility (over expected life)	22.30%	19.40%	19.80%
Expected dividend yield (over expected life)	4.20%	3.10%	3.10%
Award Year 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Performance Relative to the Peer Group (1%Best)			57.00%
Payout as a Percent of the Base Award			61.00%
Number of Shares Distributed (in shares)			0.0
Cash Portion			$ 6.9
Award Year 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Performance Relative to the Peer Group (1%Best)		78.00%
Payout as a Percent of the Base Award		0.00%
Number of Shares Distributed (in shares)		0.0
Cash Portion		$ 0.0
Award Year 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Performance Relative to the Peer Group (1%Best)	63.00%
Payout as a Percent of the Base Award	49.00%
Number of Shares Distributed (in shares)	0.1	0.1
Cash Portion	$ 1.6	$ 2.2
TSR based \| Performance Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares base award (in shares)	0.1	0.1	0.1
Grant date per share fair value (in dollars per share)	$ 57.86	$ 42.60	$ 50.75
Risk-free interest rate	2.40%	2.40%	1.50%
Expected life in years	3 years	3 years	3 years
Expected volatility (over expected life)	21.50%	19.90%	19.50%
Expected dividend yield (over expected life)	3.40%	3.30%	2.80%
EBIT CAGR based \| Performance Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares base award (in shares)	0.1	0.1
Grant date per share fair value (in dollars per share)	$ 39.98	$ 40.92
Vesting period in years	3 years	3 years

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- Definition

Three year performance cycle total shareholder return performance relative to the peer group one percent equal to best.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Amount of cash paid to settle liability for award under share-based payment arrangement.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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