Leases and Other Commitments - Summary of Future Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Office Leases
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	$ 6,985
2020	6,371
2021	8,331
2022	6,939
2023	6,987
Thereafter	65,151
Total	100,764
Total	100,764
Equipment Leases
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	216
2020	22
2021	0
2022	0
2023	0
Thereafter	0
Total	238
Total	238
Lease Related Commitments
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	29,587
2020	0
2021	0
2022	0
2023	0
Thereafter	0
Total	29,587
Tenant Improvement Allowance	(14,441)
Total	$ 15,146

Operating Leases, Future Minimum Payments Due, Before Tenant Allowance

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Tenant Improvement Allowance

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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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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.

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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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