Fair Value Measurements (Fair Value of Assets and Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets:
Short-term investments		$ 7.5us-gaap_ShortTermInvestments
Derivative Instruments in Hedges, Assets, at Fair Value	0.2
Deferred compensation assets	6.6us-gaap_AssetsHeldInTrustNoncurrent	5.7us-gaap_AssetsHeldInTrustNoncurrent
Total assets at fair value	6.8	13.2
Liabilities:
Contingent consideration	5.0	4.3
Deferred compensation liabilities	8.7	7.8
Interest rate swap contracts	3.6	5.6
Total liabilities at fair value	17.3us-gaap_LiabilitiesFairValueDisclosure	17.7us-gaap_LiabilitiesFairValueDisclosure
Other Financial Instruments [Abstract]
Long-term debt, fair value	311.4us-gaap_LongTermDebtFairValue	365.8us-gaap_LongTermDebtFairValue
Long-term debt	309.5us-gaap_LongTermDebtNoncurrent	371.3us-gaap_LongTermDebtNoncurrent
Level 1 [Member]
Assets:
Short-term investments		7.5
Derivative Instruments in Hedges, Assets, at Fair Value	0
Deferred compensation assets	6.6	5.7
Total assets at fair value	6.6	13.2
Liabilities:
Deferred compensation liabilities	8.7	7.8
Total liabilities at fair value	8.7	7.8
Level 2 [Member]
Assets:
Derivative Instruments in Hedges, Assets, at Fair Value	0.2
Total assets at fair value	0.2
Liabilities:
Interest rate swap contracts	3.6	5.6
Total liabilities at fair value	3.6	5.6
Level 3 [Member]
Liabilities:
Contingent consideration	5.0	4.3
Total liabilities at fair value	$ 5.0	$ 4.3

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This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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The amount of cash, securities, or other assets held by a third-party trustee pursuant to the terms of an agreement which assets are available to be used by beneficiaries to that agreement only within the specific terms thereof and which agreement is expected to terminate more than one year from the balance sheet date (or operating cycle, if longer) at which time the assets held-in-trust will be released or forfeited.

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-Section S99

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Fair value of financial and nonfinancial obligations.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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Aggregate fair value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

+ References

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