Commitments and Contingencies - Future Minimum Operating Lease Payments (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Minimum Lease Commitments
2019	$ 1,177
2020	975
2021	804
2022	325
2023 & thereafter	16
Total contractual obligations	3,297
Sublease Payments
2019	399
2020	267
2021	134
2022	0
2023 & thereafter	0
Total contractual obligations	800
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity, Net [Abstract]
2019	778
2020	708
2021	670
2022	325
2023 & thereafter	16
Total contractual obligations	$ 2,497

Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity, Net [Abstract]

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due In Four Years

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due In Three Years

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due In Two Years

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due Thereafter

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Fiscal Year Maturity [Abstract]

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Next Twelve Months

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Operating Leases, Future Minimum Payments Due, Net

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

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

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

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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 for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Contractually required future rental payments receivable on noncancelable subleasing arrangements.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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