Unaudited Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 29,939	$ 34,887
Investments	108,500	122,800
Accounts receivable, net of allowance for doubtful accounts of $223 and $479, respectively	15,111	13,614
Prepaid expenses and prepaid income taxes	9,680	10,144
Deferred contract costs	6,591	5,253
Other current assets	8,835	7,410
Restricted cash	750	750
Total current assets	179,406	194,858
Property and equipment, net	26,550	24,269
Intangible assets	4,407
Goodwill	15,852
Operating lease right-of-use assets	50,742
Restricted cash	1,918	1,921
Deferred tax assets	42,714	38,886
Deferred contract costs, net of current portion	8,446	7,252
Other long–term assets	1,892	1,104
Total assets	331,927	268,290
Current liabilities
Accounts payable	35,253	34,345
Accrued expenses, accrued income taxes and other current liabilities	13,793	18,654
Deferred revenue	8,942	8,811
Operating lease liabilities	7,486	1,693
Total current liabilities	65,474	63,503
Operating lease liability non-current	52,956	9,395
Deferred tax liabilities	1,002
Other non–current liabilities	1,486	1,281
Total liabilities	120,918	74,179
Commitments and contingencies (Note 8)
Stockholders’ equity:
Additional paid-in capital	188,954	184,216
Retained earnings	22,297	9,713
Accumulated other comprehensive (loss) income	(353)	71
Total stockholders’ equity	211,009	194,111
Total liabilities and stockholders’ equity	331,927	268,290
Class A Common Stock
Stockholders’ equity:
Common stock	90	90
Class B Common Stock
Stockholders’ equity:
Common stock	$ 21	$ 21