Our Business (Details)	Mar. 31, 2013 servicecenter language country	Dec. 31, 2012 language country servicecenter
Our Business
Languages supported	35	35
Number of service centers	56	51
Number of countries	23	22

The number of countries in which the entity operates as of balance sheet date.

No definition available.

Name:	us-gaap_NumberOfCountriesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant