Commitments And Contingencies (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Minimum Operating Lease Payments
Minimum operating lease payments, 2013	$ 9,113
Minimum operating lease payments, 2014	7,941
Minimum operating lease payments, 2015	8,147
Minimum operating lease payments, 2016	7,918
Minimum operating lease payments, 2017	8,118
Minimum operating lease payments, Thereafter	720
Total minimum operating lease payments,	41,957
Future Minimum Sublease Rentals
Sublease income, 2013	415
Sublease income, 2014	429
Sublease income, 2015	434
Sublease income, 2016	439
Sublease income, 2017	0
Sublease income, Thereafter	0
Total Sublease Income	1,717
Minimum Net Operating Lease Payments
Net operating lease payments, 2013	8,698
Net operating lease payments, 2014	7,512
Net operating lease payments, 2015	7,713
Net operating lease payments, 2016	7,479
Net operating lease payments, 2017	8,118
Net operating lease payments, Thereafter	720
Total net operating lease payments	$ 40,240

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Operating Leases, Future Minimum Payments Due, Net, Next Twelve Months

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Operating Leases, Future Minimum Payments, Net, Due in Five Years

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Operating Leases, Future Minimum Payments, Net, Due in Four Years

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Operating Leases, Future Minimum Payments, Net, Due in Three Years

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Operating Leases, Future Minimum Payments, Net, Due in Two Years

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Operating Leases, Future Minimum Payments, Net, Due Thereafter

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

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Future rental payments receivable within one year of the balance sheet date under an operating lease.

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Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the third year from the balance sheet date under an operating lease.

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Future rental payments receivable within the second year from the balance sheet date under an operating lease.

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Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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