Fair Value Measurments (Contingent Consideration)(Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Fair Value Disclosures [Abstract]
Balance as of January 1	$ 25,617	$ 5,809
Additions	6,653	19,853
Payments	(15,716)	(5,742)
Changes in fair value	6,329	5,634
Foreign currency translation adjustment	828	63
Balance as of December 31	$ 23,711	$ 25,617