Contingencies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	0 Months Ended
Mar. 31, 2013	Apr. 22, 2013 Patent Infringement [Member]
Loss Contingencies [Line Items]
Litigation Settlement (charge)	$ (1.5)	$ (1.5)
Litigation settlement amount (charge), net of tax	$ (1.0)	$ (1.0)
Litigation settlement amount, impact on diluted earnings per share		$ 0.04

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

No definition available.

Name:	us-gaap_LitigationSettlementAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration