Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Average fixed interest rate related to the group of interest rate derivatives.

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No definition available.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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-Paragraph 4C
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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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- Definition

Variable interest rate in effect as of the balance sheet date related to the interest rate derivative.

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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.

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No definition available.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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-Publisher FASB
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Fair Value Measurements (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Millions	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Derivatives Fair Value
Loss to be reclassified during next 12 months	$ 1.7		$ 1.7
Interest rate swap
Derivatives Fair Value
Gains recorded in accumulated other comprehensive loss, net of tax	0.8	$ 2.7	3.6	$ 6.3
Derivative liability fair value	1.7		1.7		$ 6.9
Interest rate swap \| Accrued liabilities
Derivatives Fair Value
Derivative liability fair value	1.7		1.7		6.7
Interest rate swap \| Other long-term liabilities
Derivatives Fair Value
Derivative liability fair value	0.0		0.0		0.2
Interest rate swap \| Interest Expense
Derivatives Fair Value
Ineffectiveness recorded in interest expense	(0.2)	0.0	0.5	0.0
Reclassifications of losses out of accumulated other comprehensive loss	1.7	2.0	5.8	6.1
Ineffectiveness recorded in interest expense	$ (0.2)	$ 0.0	$ 0.5	$ 0.0
Interest rate swap \| LIBOR
Derivatives Fair Value
Interest received on derivative	1.00%		1.00%
Interest rate swap \| Cash Flow Hedging \| Designated as Hedging Instrument
Derivatives Fair Value
Derivative average fixed interest rate	2.151%		2.151%
Total notional amount of swaps	$ 700.0		$ 700.0		$ 700.0