Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 815
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Fixed interest rate related to the interest rate derivative.

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Nominal or face amount used to calculate payment on derivative.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

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-Topic 815
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Financial Instruments and Fair Value Measurements - Derivative Financial Instruments (Details) - Cash flow hedge £ in Millions, $ in Millions	Jun. 30, 2019 USD ($)	May 31, 2019 GBP (£)	May 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Designated as hedging instrument
Derivative [Line Items]
Notional Amount	$ 673.5			$ 507.2
Fair Value - asset (liability)	(11.4)			(4.0)
Interest rate swap, maturity Sep 2021 \| Designated as hedging instrument
Derivative [Line Items]
Notional Amount	$ 7.1			7.2
Strike (percent)	6.03%
Fair Value - asset (liability)	$ (0.3)			(0.2)
Interest rate swap, maturity Jun 2020 \| Designated as hedging instrument
Derivative [Line Items]
Notional Amount	$ 250.0			250.0
Strike (percent)	1.72%
Fair Value - asset (liability)	$ 0.4			3.0
Interest rate swap, maturity Mar 2024 \| Designated as hedging instrument
Derivative [Line Items]
Notional Amount	$ 250.0			250.0
Strike (percent)	3.04%
Fair Value - asset (liability)	$ (15.5)			(6.8)
Cross-currency swap, maturity May 2034 1 \| Designated as hedging instrument
Derivative [Line Items]
Notional Amount	41.6			0.0
Fair Value - asset (liability)	$ 1.2			0.0
Cross-currency swap, maturity May 2034 1 \| Designated as hedging instrument \| GBP \| Minimum
Derivative [Line Items]
Strike (percent)	4.82%
Cross-currency swap, maturity May 2034 1 \| Designated as hedging instrument \| GBP \| Maximum
Derivative [Line Items]
Strike (percent)	10.96%
Cross-currency swap, maturity May 2034 1 \| Designated as hedging instrument \| USD
Derivative [Line Items]
Strike (percent)	9.80%
Cross-currency swap, maturity May 2034 2 \| Designated as hedging instrument
Derivative [Line Items]
Notional Amount	$ 41.6			0.0
Fair Value - asset (liability)	$ 1.3			0.0
Cross-currency swap, maturity May 2034 2 \| Designated as hedging instrument \| GBP \| Minimum
Derivative [Line Items]
Strike (percent)	4.82%
Cross-currency swap, maturity May 2034 2 \| Designated as hedging instrument \| GBP \| Maximum
Derivative [Line Items]
Strike (percent)	10.96%
Cross-currency swap, maturity May 2034 2 \| Designated as hedging instrument \| USD
Derivative [Line Items]
Strike (percent)	9.803%
Cross-currency swap, maturity May 2034 3 \| Designated as hedging instrument
Derivative [Line Items]
Notional Amount	$ 41.6			0.0
Fair Value - asset (liability)	$ 0.9			0.0
Cross-currency swap, maturity May 2034 3 \| Designated as hedging instrument \| GBP \| Minimum
Derivative [Line Items]
Strike (percent)	4.82%
Cross-currency swap, maturity May 2034 3 \| Designated as hedging instrument \| GBP \| Maximum
Derivative [Line Items]
Strike (percent)	10.96%
Cross-currency swap, maturity May 2034 3 \| Designated as hedging instrument \| USD
Derivative [Line Items]
Strike (percent)	9.745%
Cross-currency swap, maturity May 2034 4 \| Designated as hedging instrument
Derivative [Line Items]
Notional Amount	$ 41.6			0.0
Fair Value - asset (liability)	$ 0.6			$ 0.0
Cross-currency swap, maturity May 2034 4 \| Designated as hedging instrument \| GBP \| Minimum
Derivative [Line Items]
Strike (percent)	4.82%
Cross-currency swap, maturity May 2034 4 \| Designated as hedging instrument \| GBP \| Maximum
Derivative [Line Items]
Strike (percent)	10.96%
Cross-currency swap, maturity May 2034 4 \| Designated as hedging instrument \| USD
Derivative [Line Items]
Strike (percent)	9.755%
Cross-currency swaps
Derivative [Line Items]
Notional Amount		£ 130	$ 166.0