The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months, net of tax.

No definition available.

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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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.

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- Definition

The net cash outflow or inflow for a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3098-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 27
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3581-108585

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3095-108585

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Derivative Instruments and Hedging Activities - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2008
Derivative [Line Items]
Net amount of settlement gains (losses) on derivative instruments included in accumulated OCI to be amortized over next 12 months, before tax	$ (5.3)
Net amount of settlement gains (losses) on derivative instruments included in accumulated OCI to be amortized over next 12 months, after tax	$ (3.3)
2008 Interest Rate Protection Agreement
Derivative [Line Items]
Payments for (Proceeds from) settlement of interest rate protection agreement				$ 4.4
2010 Interest Rate Protection Agreement
Derivative [Line Items]
Payments for (Proceeds from) settlement of interest rate protection agreement			$ (9.9)
2011 Interest Rate Protection Agreement
Derivative [Line Items]
Payments for (Proceeds from) settlement of interest rate protection agreement		$ 65.5