Fair Value Disclosure - Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($) Instrument	Dec. 31, 2018 USD ($) Instrument
Derivative [Line Items]
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months	$ 1.8
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months, net of tax	$ 1.3
Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Number of derivative instruments \| Instrument	8	9
Derivative liability	$ 450.0	$ 500.0
Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Number of derivative instruments \| Instrument	12	8
Derivative liability	$ 523.5	$ 501.9
Not Designated as Hedging Instrument [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Derivative liability	$ 3.7

Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months, Gross

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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.

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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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