Acquisitions Acquisitions Narrative (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Business Acquisition [Line Items]
Number of Businesses Acquired	2	6
IAN
Business Acquisition [Line Items]
Number of Businesses Acquired	2	6
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	$ 45.0	$ 53.0

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant