Derivative Instruments and Hedging Activities - Gains and losses on derivatives (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Gains and losses on derivatives
Tax expense	$ 0.9	$ 3.1
Loss reclassified from AOCL into income, net	3.0	3.1
Interest expense
Gains and losses on derivatives
Loss recorded in AOCL on derivatives, before tax	3.9	6.2
Interest rate swaps \| Hedging \| Cash flow hedging
Gains and losses on derivatives
Losses on derivative	$ 3.8	$ 0.7

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Amount of decrease in the fair value of derivatives recognized in the income statement.

+ References

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-Publisher FASB
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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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