Fair Value Measurements (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Fair Value Measurements [Abstract]
Accrued earnouts	$ 26.9		$ 30.1
Performance targets, maximum potential obligation	38.6
Impairment charge recognized, related to long-lived assets	3.6	3.7
Write-offs relating to long-lived assets and intangibles	2.3	0.8
Certificate of deposits	4.9		5.2
Held-to-maturity investments, carrying value	1.2		1.1
Held-to-maturity investments, fair value	$ 1.3		$ 1.3
Interest rate under Revolving Credit Facility	1.875%

A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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