Commitments and Contingencies - Reorganization (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019
Lease Exit Costs
Restructuring Reserve [Roll Forward]
Ending balance			$ 800
Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs	$ 4,600
Restructuring Reserve [Roll Forward]
Beginning balance		$ 0	0
Expense			7,871
Cash Payments			(7,843)
Ending balance			$ 28
Sales and Marketing | Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs	400
Technology and development | Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs	900
General and administrative | Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs	3,300
Reorganization Plan | Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs		$ 3,300
Reorganization Plan | Cost of revenue | Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs	400
Reorganization Plan | Sales and Marketing | Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs	1,100
Reorganization Plan | Technology and development | Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs	1,600
Reorganization Plan | General and administrative | Employee severance
Restructuring Cost and Reserve [Line Items]
Severance Costs	$ 200