Leases (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) ft² location
Lessee, Lease, Description [Line Items]
Operating lease liabilities, current portion included in other accrued liabilities | $	$ 5,147
Operating lease liabilities, long-term portion | $	30,674
Operating lease liabilities | $	$ 35,821
Weighted average remaining lease term	3 years 5 months 23 days
Weighted average discount rate (as a percent)	10.77%
Lease expense | $	$ 1,900
Operating lease payments | $	$ 2,100
Corporate Headquarters Lease
Lessee, Lease, Description [Line Items]
Office space (area) | ft²	113,000
Number of office space locations | location	2
Term of lease	84 months
Renewal term of lease	5 years
"First Space" Sublease
Lessee, Lease, Description [Line Items]
Office space (area) | ft²	88,000
"Second Space" Sublease
Lessee, Lease, Description [Line Items]
Office space (area) | ft²	25,000
Tukwila, WA lease
Lessee, Lease, Description [Line Items]
Office space (area) | ft²	10,000
Term of lease	62 months
Renewal term of lease	5 years
Austin TX, Long-term Lease
Lessee, Lease, Description [Line Items]
Office space (area) | ft²	94,000
Term of lease	132 months