Basis of Presentation and Summary of Significant Accounting Policies - Summary of Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Contract assets:
Beginning balance	$ 1,666	$ 1,666	$ 1,956
Additions	10,029	11,670
Deductions	(10,319)	(9,423)	(10,300)
Ending balance		3,913	1,666
Contract liabilities:
Beginning balance	1,175	1,175	1,280
Additions	3,032	4,437
Deductions	$ (3,137)	(4,239)	(3,100)
Ending balance		1,373	$ 1,175
Amounts reclassified from unbilled revenue to accounts receivable		(9,400)
Amounts reclassified from deferred revenue to revenue		$ (4,200)