Earnings Per Share and Shareholders' Equity Transactions (Information Regarding Basic and Diluted Earnings Per Share) (Details) - $ / shares shares in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Basic shares used in the calculation of earnings per share	40.6	42.5
Diluted shares used in the calculation of earnings per share	41.2	43.1
Per share effect of dilutive securities on income from continuing operations and net income	$ (0.04)	$ (0.02)
Employee Stock Option [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Dilutive effect of securities	0.3	0.3
Non-Vested Stock Grants [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Dilutive effect of securities	0.3	0.3

Per share effect of dilutive securities on income from continuing operations and net income.

No definition available.

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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

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 28A
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1500-109256

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-Section 50
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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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