Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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New Accounting Guidance (Narratives) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2017	Mar. 31, 2017	Oct. 01, 2016	Sep. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefits recognized under new accounting standard	$ 2.7	$ 9.7
Accounting Standards Update 2015-03 [Member] \| Other Noncurrent Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of debt issuance cost with (decrease) to assets and decrease to liabilities				$ (17.0)
Accounting Standards Update 2015-03 [Member] \| Other Noncurrent Assets [Member] \| Discontinued Operations [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of debt issuance cost with (decrease) to assets and decrease to liabilities				(9.6)
Accounting Standards Update 2015-03 [Member] \| Long-term Debt [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of debt issuance cost with (decrease) to assets and decrease to liabilities				17.0
Accounting Standards Update 2015-03 [Member] \| Noncurrent Liabilities [Member] \| Discontinued Operations [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of debt issuance cost with (decrease) to assets and decrease to liabilities				$ 9.6
Accounting Standards Update 2016-09 [Member] \| New Accounting Pronouncement, Early Adoption, Effect [Member] \| Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment related to adoption of new accounting standard			$ 8.8