Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current Assets:
Cash and cash equivalents	$ 79,960	$ 76,958
Marketable investments (Note 3)	54,019	61,147
Accounts receivable, net	39,481	58,812
Deferred commissions	9,146	12,052
Prepaid expenses and other current assets	15,817	14,467
Total current assets	198,423	223,436
Property and equipment, net	26,128	23,894
Goodwill	75,815	73,193
Intangible assets, net	927	1,464
Other assets	13,095	13,798
Total assets	314,388	335,785
Current Liabilities:
Accounts payable	613	1,806
Accrued expenses and other current liabilities	36,838	41,403
Deferred revenue	132,929	134,265
Total current liabilities	170,380	177,474
Non-current liabilities	8,788	8,275
Total liabilities	179,168	185,749
Stockholders' Equity (Note 7):
Preferred stock, $0.01 par value Authorized - 500 shares; issued and outstanding - none
Common stock, $0.01 par value Authorized - 125,000 shares Issued - 22,293 and 21,719 shares as of September 30, 2017 and December 31, 2016, respectively Outstanding - 17,902 and 18,361 shares as of September 30, 2017 and December 31, 2016, respectively	223	217
Additional paid-in capital	175,218	157,569
Retained earnings	124,343	121,799
Treasury stock - 4,391 and 3,358 shares as of September 30, 2017 and December 31, 2016, respectively, at cost	(161,943)	(121,976)
Accumulated other comprehensive loss	(2,621)	(7,573)
Total stockholders’ equity	135,220	150,036
Total liabilities and stockholders’ equity	$ 314,388	$ 335,785

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.