Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Property and Equipment [Line Items]
Total property and equipment	$ 147,580		$ 140,169
Accumulated depreciation and amortization expenses	(61,772)		(55,014)
Total property and equipment, net	85,808		85,155
Depreciation expense	6,800	$ 5,200
Capitalized computer software, amortization	5,600	4,100
Computer hardware
Property and Equipment [Line Items]
Total property and equipment	11,851		11,604
Furniture and equipment
Property and Equipment [Line Items]
Total property and equipment	3,590		3,649
Internal-use software development costs
Property and Equipment [Line Items]
Total property and equipment	119,801		112,501
Total property and equipment, net	76,600		74,900
Capitalized computer software additions	7,300	$ 8,700
Leasehold improvements
Property and Equipment [Line Items]
Total property and equipment	$ 12,338		$ 12,415