Interim Financial Statements (Recent Accounting Pronouncements) (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($)
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax deficiency from stock-based awards	$ 0.3
Cumulative effect on retained earnings (pre-tax), share-based accounting standard	0.2
Accounting Standards Update 2016-02 [Member] \| Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability	300.0
Accounting Standards Update 2016-02 [Member] \| Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability	$ 400.0

Amount of excess tax benefit (deficiency) associated with share-based compensation, which is included as a component of income tax provision on the income statement.

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Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

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- Definition

Amount of the cumulative effect on retained earnings before related income tax effect.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794

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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.

+ References

No definition available.

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