Income Taxes (Reconciliation of unrecognized tax benefits) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning Balance	$ 10,177	$ 9,173
Additions based on tax positions related to the current year	1,593	2,233
Additions for prior years tax positions	3,945	0
Reductions for prior years tax positions	(1,124)	(1,229)
Ending Balance	$ 14,591	$ 10,177