CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 93,677	$ 216,226
Marketable securities	131,190	29,414
Accounts receivable, net of allowance for doubtful accounts of $1,269 and $763 as of December 31, 2016 and 2015, respectively	37,343	26,168
Prepaid expenses and other current assets	17,608	11,423
Total current assets	279,818	283,231
Marketable securities, noncurrent	75,168	22,336
Property and equipment, net	62,731	56,540
Goodwill and intangible assets, net	53,296	57,050
Other assets	4,272	3,529
Total assets	475,285	422,686
Current liabilities:
Accounts payable	4,555	9,332
Accrued liabilities	19,106	9,742
Accrued compensation and related benefits	20,281	14,115
Deferred revenue	123,276	84,210
Total current liabilities	167,218	117,399
Deferred revenue, noncurrent	1,257	1,405
Other liabilities	7,382	10,592
Total liabilities	175,857	129,396
Commitments and contingencies (Note 8)
Stockholders’ equity:
Preferred stock, par value $0.01 per share: no shares issued or outstanding; 10.0 million shares authorized as of December 31, 2016 and 2015	0	0
Common stock, par value $0.01 per share: 400.0 million shares authorized; 97.2 million and 90.9 million shares issued; 96.7 million and 90.3 million shares outstanding as of December 31, 2016 and 2015, respectively (including 0.1 million and 0.3 million shares subject to repurchase, legally issued and outstanding as of December 31, 2016 and 2015, respectively)	971	905
Additional paid-in capital	624,026	511,183
Accumulated other comprehensive loss	(5,197)	(2,225)
Accumulated deficit	(319,720)	(215,921)
Treasury stock, at cost; 0.5 million shares as of December 31, 2016 and 2015	(652)	(652)
Total stockholders’ equity	299,428	293,290
Total liabilities and stockholders’ equity	$ 475,285	$ 422,686

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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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.