Summary of Significant Accounting Policies - Opening and Closing Balances of the Company's Contract Assets and Deferred Revenue (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Contract assets, current portion
Beginning balance	$ 0
Ending balance	187
Change	187
Contract assets
Beginning balance	3,997
Ending balance	4,183
Change	186
Deferred Revenue, Current
Beginning balance	14,870
Ending balance	14,273
Change	(597)
Deferred Revenue
Beginning balance	23,862
Ending balance	25,880
Change	2,018
Deferred revenue related to leases, current portion	1,200	$ 1,700
Deferred revenue related to leases, noncurrent portion	$ 3,100	$ 2,700