Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Fair Value of Financial Instruments [Line Items]
Long-term debt, fixed interest rate	3.75%	3.65%
Notes payable, fair value	$ 894.4	$ 886.4
Notes payable, carrying value	$ 824.5	$ 784.8
Interest Rate Swap
Fair Value of Financial Instruments [Line Items]
Interest rate swap agreement, termination date	Jul. 01, 2020
Fair value of derivative liability	$ 3.6

Fair Value of Financial Instruments [Line Items]

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- Definition

Interest Rate Swap Agreement Termination Date

+ References

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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-Section 50

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-Name Accounting Standards Codification

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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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.22(a)(1))

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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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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher SEC

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- Definition

Fair value portion of notes payable.

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