Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 956,956	$ 368,518
Short-term investments, available-for-sale	727,073	502,852
Accounts receivable, net of allowances of $5,883 and $7,719 at December 31, 2016 and 2015, respectively	725,940	669,276
Inventories, net	12,522	10,521
Prepaid expenses and other current assets	138,786	132,784
Total current assets	2,561,277	1,683,951
Long-term investments, available-for-sale	980,142	891,964
Property and equipment, net	343,820	373,817
Goodwill	1,966,810	1,962,722
Other intangible assets, net	227,993	283,418
Deferred tax assets, net	252,396	215,196
Other assets	57,789	56,449
Total assets	6,390,227	5,467,517
Current liabilities:
Accounts payable	84,057	95,396
Accrued expenses and other current liabilities	302,887	317,468
Income taxes payable	39,771	18,351
Current portion of deferred revenues	1,323,478	1,249,754
Convertible notes, short-term	1,348,156	0
Total current liabilities	3,098,349	1,680,969
Long-term portion of deferred revenues	480,359	414,314
Convertible notes, long-term	0	1,311,071
Other liabilities	123,297	87,717
Commitments and contingencies
Temporary equity from Convertible notes	79,495	0
Preferred stock at $.01 par value: 5,000 shares authorized, none issued and outstanding	0	0
Common stock at $.001 par value: 1,000,000 shares authorized; 302,851 and 299,113 shares issued and outstanding at December 31, 2016 and 2015, respectively	303	299
Additional paid-in capital	4,761,588	4,566,919
Retained earnings	4,010,737	3,474,625
Accumulated other comprehensive loss	(28,704)	(28,527)
Stockholders' equity before treasury stock	8,743,924	8,013,316
Less - common stock in treasury, at cost (146,552 and 145,296 shares at December 31, 2016 and 2015, respectively)	(6,135,197)	(6,039,870)
Total stockholders' equity	2,608,727	1,973,446
Total liabilities, temporary equity and stockholders' equity	$ 6,390,227	$ 5,467,517

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.