CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 181,192	$ 160,355
Accounts receivable, net	45,339	30,243
Prepaid expenses and other current assets	21,512	15,313
Total current assets	248,043	205,911
Property and equipment, net	43,298	31,994
Goodwill	9,393	9,393
Acquired intangibles, net	1,462	2,244
Other assets	2,972	3,087
Total assets	305,168	252,629
Current liabilities
Accounts payable	7,322	7,810
Accrued liabilities	54,977	48,322
Current portion of capital lease obligation		181
Current portion of long-term debt		14,528
Deferred revenue	64,415	45,159
Total current liabilities	126,714	116,000
Long-term debt		312
Other long-term liabilities	6,252	6,276
Total liabilities	132,966	122,588
Commitments and contingencies (Note 8)
Stockholders' equity:
Additional paid-in capital	434,840	366,800
Accumulated other comprehensive income	2,998	2,737
Accumulated deficit	(265,644)	(239,503)
Total stockholders' equity	172,202	130,041
Total liabilities and stockholders' equity	305,168	252,629
Class A common stock
Stockholders' equity:
Common stock	7	6
Class B common stock
Stockholders' equity:
Common stock	$ 1	$ 1

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.