Commitments (Schedule Of Future Minimum Lease Payments Under Noncancelable Operating Leases And Future Minimum Capital Lease Payments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Commitments [Abstract]
Capital Leases, 2012	$ 1,520
Capital Leases, 2013	1,550
Capital Leases, 2014	1,581
Capital Leases, 2015	1,613
Capital Leases, 2016	1,645
Capital Leases, Thereafter	11,051
Capital Leases, Total minimum lease payments	18,960
Less: amount representing interest	7,941
Present value of minimum lease payments	11,019
Less: current installments	419	362
Capital lease obligations, less current installments	10,600	11,019
Operating Leases, 2012	8,801
Operating Leases, 2013	6,177
Operating Leases, 2014	5,032
Operating Leases, 2015	4,668
Operating Leases, 2016	3,420
Operating Leases, Thereafter	3,517
Operating Leases, Total minimum lease payments	$ 31,615

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid within one year (or one operating cycle, if longer) of the balance sheet date.