Commitments and Contingencies - Operating Leases (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Commitments and Contingencies Disclosure [Abstract]
Operating Leases, Rent Expense	$ 5,189	$ 5,282	$ 5,112
Future Operating Lease Minimum Payments, Due Next Year	4,927
Future Operating Lease Minimum Payments, Due in Two Years	4,003
Future Operating Lease Minimum Payments, Due in Three Years	3,472
Future Operating Lease Minimum Payments, Due in Four Years	2,941
Future Operating Lease Minimum Payments, Due in Five Years	1,466
Future Operating Lease Minimum Payments, Due Therafter	$ 2