Accumulated Other Comprehensive Income (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation adjustments	$ (6,368)	$ (2,354)
Net unrealized gain on investments, net of taxes of $(552) at September 30, 2012 and $(14) at December 31, 2011	785	714
Total accumulated other comprehensive income (loss)	(5,583)	(1,640)
Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Tax	$ (428)	$ (418)