Notes Payable and Other Obligations (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Future minimum lease payments under non-cancelable notes payable, operating and capital leases
2013 Notes and Capital Leases	$ 165
2014 Notes and Capital Leases	89
2015 Notes and Capital Leases	33
Total future minimum lease payments, Notes and Capital Leases	287
Less amount representing interest	(29)
Present value of net minimum lease payments	258
Less current portion	144	131
Notes payable and other obligations	114	258
2013 Operating Leases	1,806
2014 Operating Leases	1,875
2015 Operating Leases	1,406
Total future minimum lease payments, Operating Lease	$ 5,087

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.

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