Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Fair Value of Financial Instruments [Line Items]
Notes payable, fixed interest rate	4.55%	3.90%
Notes payable, aggregate fair value	$ 891.9	$ 951.7
Notes payable, principal balance	870.9	$ 890.4
Interest Rate Swap
Fair Value of Financial Instruments [Line Items]
Fair value of derivative liability	$ 0.3

Fair Value of Financial Instruments [Line Items]

No definition available.

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- Definition

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.

+ References

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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- Definition

Fair value portion of notes payable.

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