Commitments and Contingencies - Schedule of Future Minimum Payments Required Under Leases (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Commitments And Contingencies Disclosure [Abstract]
Operating Lease, 2018	$ 3,579
Operating Lease, 2019	3,626
Operating Lease, 2020	3,675
Operating Lease, 2021	3,684
Operating Lease, 2022	3,307
Operating Lease, Thereafter	12,573
Operating Lease, Total	30,444
Lease Payments to be Received from Sublease, 2018	257
Lease Payments to be Received from Sublease, Total	257
Net Operating Lease Payments, 2018	3,322
Net Operating Lease Payments, 2019	3,626
Net Operating Lease Payments, 2020	3,675
Net Operating Lease Payments, 2021	3,684
Net Operating Lease Payments, 2022	3,307
Net Operating Lease Payments, Thereafter	12,573
Net Operating Lease Payments, Total	$ 30,187

Operating leases future minimum sublease rental income due current.

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Operating leases net future minimum payments due.

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Operating leases net future minimum payments due in five years.

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Operating leases net future minimum payments due in four years.

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Operating leases net future minimum payments due in three years.

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Operating leases net future minimum payments due in two years.

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Operating leases net future minimum payments 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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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 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717

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-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

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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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