Ziff Davis (ZD) 10-K 1 Mar 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 26, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Entity Registrant Name	J2 GLOBAL, INC.
Entity Central Index Key	1,084,048
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		49,095,551
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 2,558,879,917

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Cash and cash equivalents	$ 350,945	$ 123,950
Accounts receivable, net of allowances of $8,701 and $7,988, respectively	234,195	199,871
Prepaid expenses and other current assets	35,287	24,178
Total current assets	620,427	347,999
Long-term investments	57,722	0
Property and equipment, net	79,773	68,094
Trade names, net	123,947	115,853
Patent and patent licenses, net	10,871	13,928
Customer relationships, net	193,606	208,155
Goodwill	1,196,611	1,122,810
Other purchased intangibles, net	157,327	173,755
Deferred income taxes	0	5,289
Other assets	12,809	6,445
Total assets	2,453,093	2,062,328
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	169,837	178,071
Income taxes payable, current	0	16,753
Deferred revenue, current	95,255	80,384
Line of credit	0	178,817
Other current liabilities	10	64
Total current liabilities	265,102	454,089
Long-term debt	1,001,944	601,746
Deferred revenue, non-current	47	1,588
Income taxes payable, non-current	43,781	0
Liability for uncertain tax positions	52,216	46,537
Deferred income taxes	38,264	40,357
Other long-term liabilities	31,434	3,475
Total liabilities	1,432,788	1,147,792
Commitments and contingencies	0	0
Common stock, $0.01 par value. Authorized 95,000,000 at December 31, 2017 and 2016; total issued and outstanding 47,854,510 and 47,443,716 shares at December 31, 2017 and 2016, respectively.	479	474
Additional paid-in capital	325,854	308,329
Retained earnings	723,062	660,382
Accumulated other comprehensive loss	(29,090)	(54,649)
Total stockholders’ equity	1,020,305	914,536
Total liabilities and stockholders’ equity	2,453,093	2,062,328
Series A Preferred Stock [Member]
LIABILITIES AND STOCKHOLDERS' EQUITY
Preferred stock, $0.01 par value	0	0
Series B Preferred Stock [Member]
LIABILITIES AND STOCKHOLDERS' EQUITY
Preferred stock, $0.01 par value	$ 0	$ 0

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Allowance for doubtful accounts	$ 8,701	$ 7,988
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	95,000,000	95,000,000
Common stock, shares issued	47,854,510	47,443,716
Common stock, shares outstanding	47,854,510	47,443,716
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Treasury Stock, shares	0	0
Series A Preferred Stock [Member]
Preferred stock, shares authorized	6,000	6,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Series B Preferred Stock [Member]
Preferred stock, shares authorized	20,000	20,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0

Consolidated Statements Of Inco

Consolidated Statements Of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues:
Total revenues	$ 1,117,838	$ 874,255	$ 720,815
Cost of revenues	172,313	147,100	122,958
Gross profit	945,525	727,155	597,857
Operating expenses:
Sales and marketing	330,296	206,871	159,009
Research, development and engineering	46,004	38,046	34,329
General and administrative	323,517	239,672	205,137
Total operating expenses	699,817	484,589	398,475
Income from operations	245,708	242,566	199,382
Interest expense, net	67,777	41,370	42,458
Other (income) expense, net	(22,035)	(10,243)	5
Income before income taxes	199,966	211,439	156,919
Income tax expense	60,541	59,000	23,283
Net income	$ 139,425	$ 152,439	$ 133,636
Net income per common share:
Basic (in dollars per share)	$ 2.89	$ 3.15	$ 2.76
Diluted (in dollars per share)	$ 2.83	$ 3.13	$ 2.73
Weighted average shares outstanding:
Basic (in shares)	47,586,242	47,668,357	47,627,853
Diluted (in shares)	48,669,027	47,963,226	48,087,760
Cash dividends paid per common share (in dollars per share)	$ 1.52	$ 1.36	$ 1.22
Share-based compensation expense	$ 22,737	$ 13,650	$ 11,793
Cost of revenues
Share-based compensation expense	500	436	373
Sales and marketing
Share-based compensation expense	1,723	1,782	2,435
Research, development and engineering
Share-based compensation expense	1,182	904	863
General and administrative
Share-based compensation expense	$ 19,332	$ 10,528	$ 8,122

Consolidated Statement Of Compr

Consolidated Statement Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 49,871	$ 32,358	$ 31,376	$ 25,820	$ 43,158	$ 45,569	$ 33,770	$ 29,943	$ 139,425	$ 152,439	$ 133,636
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment									25,559	(23,076)	(15,058)
Change in fair value on available-for-sale investments, net of tax expense (benefit) of zero, $1,495 and ($4,556) for the years ended 2017, 2016 and 2015, respectively.									0	(2,449)	(6,939)
Other comprehensive income (loss), net of tax									25,559	(25,525)	(21,997)
Comprehensive income									$ 164,984	$ 126,914	$ 111,639

Consolidated Statement Of Comp6

Consolidated Statement Of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustment, tax	$ 0	$ 0	$ 0
Unrealized gain on available-for-sale investments, tax	$ 0	$ 1,495	$ (4,556)

Consolidated Statement Of Cash

Consolidated Statement Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net income	$ 139,425	$ 152,439	$ 133,636
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	162,041	122,091	93,213
Amortization of financing costs and discounts	11,952	9,818	9,105
Share-based compensation	22,737	13,650	11,793
Provision for doubtful accounts	13,159	13,169	6,872
Deferred income taxes, net	(21,432)	(13,779)	(17,083)
Loss on extinguishment of debt and related interest expense	7,962	0	0
Gain on sale of businesses	(27,681)	0	0
Changes in fair value of contingent consideration	2,300	4,850	16,200
Gain on available-for-sale investments	0	(7,716)	(549)
Decrease (increase) in:
Accounts receivable	(37,546)	(30,687)	(18,508)
Prepaid expenses and other current assets	4,001	(957)	1,461
Other assets	(2,712)	(497)	(3,881)
Increase (decrease) in:
Accounts payable and accrued expenses	(34,116)	6,363	8,757
Income taxes payable	14,888	25,409	3,578
Deferred revenue	941	(4,213)	(3,480)
Liability for uncertain tax positions	4,936	10,620	(5,718)
Other long-term liabilities	3,564	(18,173)	(6,335)
Net cash provided by operating activities	264,419	282,387	229,061
Cash flows from investing activities:
Maturity of investments	0	241,817	121,752
Purchases of investments	(4)	(80,918)	(135,894)
Purchases of property and equipment	(39,595)	(24,746)	(17,297)
Acquisition of businesses, net of cash received	(174,951)	(580,691)	(302,809)
Proceeds from sale of businesses, net of cash divested	58,300	0	0
Purchases of intangible assets	(2,240)	(4,321)	(1,455)
Net cash used in investing activities	(158,490)	(448,859)	(335,703)
Cash flows from financing activities:
Issuance of long-term debt, net	636,485	0	0
Repayment of debt	(255,000)	0	0
Proceeds from line of credit, net	44,981	178,710	0
Repayment of line of credit	(225,000)	0	0
Repurchase and retirement of common stock	(9,850)	(56,496)	(3,674)
Issuance of common stock under employee stock purchase plan	259	254	260
Exercise of stock options	1,108	3,570	4,958
Dividends paid	(73,469)	(65,835)	(58,826)
Deferred payments for acquisitions	(7,637)	(20,832)	(14,271)
Other	(54)	1,779	4,190
Net cash provided by (used in) financing activities	111,823	41,150	(67,363)
Effect of exchange rate changes on cash and cash equivalents	9,243	(6,258)	(4,128)
Net change in cash and cash equivalents	226,995	(131,580)	(178,133)
Cash and cash equivalents at beginning of year	123,950	255,530	433,663
Cash and cash equivalents at end of year	$ 350,945	$ 123,950	$ 255,530

Consolidated Statements Of Stoc

Consolidated Statements Of Stockholders' Equity Consolidated Statements Of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Net Income (Loss) Attributable to Parent	$ 133,636			$ 133,636
Beginning balance, shares at Dec. 31, 2014		47,409,514
Beginning balance at Dec. 31, 2014	820,235	$ 474	$ 273,304	553,584	$ (7,127)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	111,639				(21,997)
Other comprehensive income (loss), net of tax	(21,997)
Dividends	$ (58,826)			(58,826)
Exercise of stock options, shares	221,221	221,221
Exercise of stock options	$ 4,958	$ 2	4,956
Issuance of shares under Employee Stock Purchase Plan, shares		4,020
Issuance of shares under Employee Stock Purchase Plan	260	$ 0	260
Vested restricted stock, shares		278,092
Vested restricted stock		$ (3)	(3)
Repurchase and retirement of common stock, shares		(53,904)
Repurchase and retirement of common stock	(3,674)	$ (1)	(1,955)	(1,718)
Exchange of Series B preferred stock, shares		91,734
Exchange of Series B preferred stock		$ 1	1
Share based compensation	11,130		11,017	113
Excess tax benefit on share based compensation	4,486		4,486
Ending balance at Dec. 31, 2015	890,208	$ 479	292,064	626,789	(29,124)
Ending balance, shares at Dec. 31, 2015		47,950,677
Net Income (Loss) Attributable to Parent	152,439			152,439
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	126,914				(25,525)
Other comprehensive income (loss), net of tax	(25,525)
Dividends	$ (65,835)			(65,835)
Exercise of stock options, shares	142,870	142,870
Exercise of stock options	$ 3,570	$ 1	3,569
Issuance of shares under Employee Stock Purchase Plan, shares		3,918
Issuance of shares under Employee Stock Purchase Plan	254	$ 0	254
Vested restricted stock, shares		270,098
Vested restricted stock		$ (3)	(3)
Repurchase and retirement of common stock, shares		(1,015,584)
Repurchase and retirement of common stock	(56,496)	$ (10)	(3,344)	(53,142)
Exchange of Series B preferred stock, shares		91,737
Exchange of Series B preferred stock		$ 1	1
Share based compensation	13,650		13,519	131
Excess tax benefit on share based compensation	2,271		2,271
Ending balance at Dec. 31, 2016	914,536	$ 474	308,329	660,382	(54,649)
Ending balance, shares at Dec. 31, 2016		47,443,716
Net Income (Loss) Attributable to Parent	139,425			139,425
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	164,984				25,559
Other comprehensive income (loss), net of tax	25,559
Dividends	$ (73,469)			(73,469)
Exercise of stock options, shares	38,183	38,183
Exercise of stock options	$ 1,108	$ 1	1,107
Issuance of shares under Employee Stock Purchase Plan, shares		3,283
Issuance of shares under Employee Stock Purchase Plan	259	$ 0	259
Vested restricted stock, shares		397,781
Vested restricted stock		$ (4)	(4)
Repurchase and retirement of common stock, shares		(117,076)
Repurchase and retirement of common stock	(9,850)	$ (1)	(6,441)	(3,408)
Exchange of Series B preferred stock, shares		88,623
Exchange of Series B preferred stock		$ 1	1
Share based compensation	22,737		22,605	132
Ending balance at Dec. 31, 2017	$ 1,020,305	$ 479	$ 325,854	$ 723,062	$ (29,090)
Ending balance, shares at Dec. 31, 2017		47,854,510

The Company

The Company	12 Months Ended
	Dec. 31, 2017
The Company [Abstract]
The Company	The Company j2 Global, Inc., together with its subsidiaries (“j2 Global” or the “Company”), is a leading provider of internet services. Through our Cloud Services segment, we provide cloud services to consumers and businesses and license our intellectual property (“IP”) to third parties. In addition, the Cloud Services segment includes fax, voice, backup, security and email marketing products. Our Digital Media segment specializes in the technology, gaming, lifestyle and healthcare markets, offering content, tools and services to consumers and businesses.

Basis Of Presentation

Basis Of Presentation	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies [Text Block]	Basis of Presentation and Summary of Significant Accounting Policies (a) Principles of Consolidation The accompanying consolidated financial statements include the accounts of j2 Global and its direct and indirect wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. On August 10, 2016, j2 Cloud Services, Inc., a Delaware corporation and subsidiary of the Company, converted into a Delaware limited liability company which continues as j2 Cloud Services, LLC. On August 12, 2016, all of the equity interests in Ziff Davis, LLC, a Delaware limited liability company, and all of the equity interests in Advanced Messaging Technologies, Inc., a Delaware corporation, held by j2 Cloud Services, LLC, a Delaware limited liability company, were distributed to j2 Global, the parent company of j2 Cloud Services, LLC. (b) Use of Estimates The preparation of consolidated financial statements in accordance with generally accepted accounting principles in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements, including judgments about investment classifications, and the reported amounts of net revenue and expenses during the reporting period. We believe that our most significant estimates are those related to valuation and impairment of marketable securities, valuation of assets acquired and liabilities assumed in connection with business combinations, long-lived and intangible asset impairment, contingent consideration, income taxes and contingencies and allowance for doubtful accounts. On an ongoing basis, management evaluates its estimates based on historical experience and on various other factors that the Company believes to be reasonable under the circumstances. Actual results could materially differ from those estimates. (c) Allowances for Doubtful Accounts j2 Global reserves for receivables it may not be able to collect. These reserves for the Company’s Cloud Services segment are typically driven by the volume of credit card declines and past due invoices and are based on historical experience as well as an evaluation of current market conditions. These reserves for the Company’s Digital Media segment are typically driven by past due invoices based on historical experience. On an ongoing basis, management evaluates the adequacy of these reserves. (d) Revenue Recognition Cloud Services The Company’s Cloud Services revenues substantially consist of monthly recurring subscription and usage-based fees, which are primarily paid in advance by credit card. In accordance with GAAP, the Company recognizes revenue when persuasive evidence of an arrangement exists, services have been provided, the sales price is fixed and determinable and collection is probable. The Company defers the portions of monthly, quarterly, semi-annually and annually recurring subscription and usage-based fees collected in advance and recognizes them in the period earned. Additionally, the Company defers and recognizes subscriber activation fees and related direct incremental costs over a subscriber’s estimated useful life. Along with our numerous proprietary Cloud Services solutions, the Company also generates revenues by reselling various third party solutions, primarily through our email security and online backup lines of business. These third party solutions, along with our proprietary products, allow the Company to offer customers a variety of solutions to better meet their needs. The Company determines whether reseller revenue should be reported on a gross or net basis by assessing whether the Company is acting as the principal or an agent in the transaction. If the Company is acting as the principal in a transaction, the Company reports revenue on a gross basis. If the Company is acting as an agent in a transaction, the Company reports revenue on a net basis. In determining whether the Company acts as the principal or an agent, the Company follows the accounting guidance for principal-agent considerations and the Company places the most weight on three factors: whether or not the Company (i) is the primary obligor in the arrangement, (ii) has latitude in determining pricing and (iii) bears credit risk. The Company records revenue on a gross basis with respect to reseller revenue as the Company is the primary obligator in the arrangement, has latitude in determining pricing and bears all credit risk associated with our reseller program partners. j2 Global’s Cloud Services also include patent license revenues generated under license agreements that provide for the payment of contractually determined fully paid-up or royalty-bearing license fees to j2 Global in exchange for the grant of non-exclusive, retroactive and future licenses to our intellectual property, including patented technology. Patent revenues may also consist of revenues generated from the sale of patents. Patent license revenues are recognized when earned over the term of the license agreements. With regard to fully paid-up license arrangements, the Company recognizes as revenue in the period the license agreement is executed the portion of the payment attributable to past use of the intellectual property and amortizes the remaining portion of such payments on a straight-line basis, or pro-rata revenue basis, as appropriate over the life of the licensed patent(s). With regard to royalty-bearing license arrangements, the Company recognizes revenues of license fees earned during the applicable period. With regard to patent sales, the Company recognizes as revenue in the period of the sale the amount of the purchase price over the carrying value of the patent(s) sold. The Cloud Services business also generates revenues by licensing certain technology to third parties. These licensing revenues are recognized when earned in accordance with the terms of the underlying agreement. Generally, revenue is recognized as the third party uses the licensed technology over the period. Digital Media The Company’s Digital Media revenues primarily consist of revenues generated from the sale of advertising campaigns that are targeted to the Company’s proprietary websites and to those websites operated by third parties that are part of the Digital Media business’s advertising network. Revenues for these advertising campaigns are recognized as earned, either when an ad is placed for viewing by a visitor to the appropriate web page or when the visitor “clicks through” on the ad, depending upon the terms with the individual advertiser. Revenues for Digital Media business-to-business operations consist of lead-generation campaigns for IT vendors and are recognized as earned when the Company delivers the qualified leads to the customer. j2 Global also generates Digital Media revenues through the license of certain assets to clients, for the clients’ use in their own promotional materials or otherwise. Such assets may include logos, editorial reviews, or other copyrighted material. Revenues under such license agreements are recognized when the assets are delivered to the client. Also, Digital Media revenues are generated through the license of certain speed testing technology which is recognized when delivered to the client through providing data services primarily to Internet Service Providers (“ISPs”) and wireless carriers which is recognized as earned over the term of the access period. The Digital Media business also generates other types of revenues, including business listing fees, subscriptions to online publications, and from other sources. Such other revenues are recognized as earned. The Company determines whether Digital Media revenue should be reported on a gross or net basis by assessing whether the Company is acting as the principal or an agent in the transaction. If the Company is acting as the principal in a transaction, the Company reports revenue on a gross basis. If the Company is acting as an agent in a transaction, the Company reports revenue on a net basis. In determining whether the Company acts as the principal or an agent, the Company follows the accounting guidance for principal-agent considerations and the Company places the most weight on three factors: whether or not the Company (i) is the primary obligor in the arrangement, (ii) has latitude in determining pricing and (iii) bears credit risk. The Company records revenue on a gross basis with respect to revenue generated (i) by the Company serving online display and video advertising across its owned-and-operated web properties, on third party sites or on unaffiliated advertising networks, (ii) through the Company’s lead-generation business and (iii) through the Company’s Digital Media licensing program. The Company records revenue on a net basis with respect to revenue paid to the Company by certain third-party advertising networks who serve online display and video advertising across the Company’s owned-and-operated web properties and certain third party sites. (e) Fair Value Measurements j2 Global complies with the provisions of Financial Accounting Standards Board (“FASB”) Accounting Standard Codification (“ASC”) Topic No. 820, Fair Value Measurements and Disclosures (“ASC 820”), in measuring fair value and in disclosing fair value measurements. ASC 820 provides a framework for measuring fair value and expands the disclosures required for fair value measurements of financial and non-financial assets and liabilities. As of December 31, 2017 , the carrying value of cash and cash equivalents, long-term investments, accounts receivable, interest receivable, accounts payable, accrued expenses, interest payable, customer deposits and long-term debt are reflected in the financial statements at cost. With the exception of long-term investments and long-term debt, cost approximates fair value due to the short-term nature of such instruments. The fair value of the Company’s outstanding debt was determined using the quoted market prices of debt instruments with similar terms and maturities, if available. As of the same dates, the carrying value of other long-term liabilities approximated fair value as the related interest rates approximate rates currently available to j2 Global. (f) Cash and Cash Equivalents j2 Global considers cash equivalents to be only those investments that are highly liquid, readily convertible to cash and with maturities of three months or less at the purchase date. (g) Investments j2 Global accounts for its investments in debt and equity securities in accordance with FASB ASC Topic No. 320, Investments - Debt and Equity Securities (“ASC 320”). Debt investments are typically comprised of corporate and governmental debt securities. Equity securities recorded as available-for-sale represent strategic equity investments. j2 Global determines the appropriate classification of its investments at the time of acquisition and evaluates such determination at each balance sheet date. Held-to-maturity securities are those investments which the Company has the ability and intent to hold until maturity and are recorded at amortized cost. Available-for-sale securities are those investments j2 Global does not intend to hold to maturity and can be sold. Available-for-sale securities are carried at fair value with unrealized gains and losses included in other comprehensive income. Trading securities are carried at fair value, with unrealized gains and losses included in investment income. Securities are accounted for on a specific identification basis, average cost method or other method, as appropriate. (h) Debt Issuance Costs and Debt Discount j2 Global capitalizes costs incurred with borrowing and issuance of debt securities and records debt issuance costs and discounts as a reduction to the debt amount. These costs and discounts are amortized and included in interest expense over the life of the borrowing or term of the credit facility using the effective interest method. (i) Derivative Instruments j2 Global currently holds an embedded derivative instrument related to contingent interest in connection with its 3.25% Convertible Notes issued on June 10, 2014. This embedded derivative instrument is carried at fair value with changes recorded to interest expense (see Note 6 - Fair Value Measurements). (j) Concentration of Credit Risk All of the Company’s cash, cash equivalents and marketable securities are invested at major financial institutions primarily within the United States, United Kingdom and Ireland. These institutions are required to invest the Company’s cash in accordance with the Company’s investment policy with the principal objectives being preservation of capital, fulfillment of liquidity needs and above market returns commensurate with preservation of capital. The Company’s investment policy also requires that investments in marketable securities be in only highly rated instruments, with limitations on investing in securities of any single issuer. However, these investments are not insured against the possibility of a total or near complete loss of earnings or principal and are inherently subject to the credit risk related to the continued credit worthiness of the underlying issuer and general credit market risks. At December 31, 2017 , the Company’s cash and cash equivalents were maintained in accounts that are insured up to the limit determined by the applicable governmental agency. The Company’s deposits held in qualifying financial institutions in Ireland are fully insured through March 28, 2018 to the extent on deposit prior to March 28, 2013. With respect to the Company’s deposits with financial institutions in other jurisdictions, the insured amount held in other institutions is immaterial in comparison to the total amount of the Company’s cash and cash equivalents held by these institutions which is not insured. These institutions are primarily in the United States and United Kingdom, however, the Company has accounts within several other countries including Australia, Austria, China, France, Germany, Italy, Japan, New Zealand and the Netherlands. (k) Foreign Currency Some of j2 Global’s foreign subsidiaries use the local currency of their respective countries as their functional currency. Assets and liabilities are translated at exchange rates prevailing at the balance sheet dates. Revenues, costs and expenses are translated into U.S. Dollars at average exchange rates for the period. Gains and losses resulting from translation are recorded as a component of accumulated other comprehensive income (loss). Net translation gain/(loss) was $25.6 million , $(23.1) million and $(15.1) million for the years ended December 31, 2017 , 2016 and 2015 , respectively. Realized gains and losses from foreign currency transactions are recognized within other (income) expense, net. Foreign exchange losses amounted to $5.8 million , $0.7 million and $0.1 million for the years ended December 31, 2017, 2016 and 2015, respectively. (l) Property and Equipment Property and equipment are stated at cost. Equipment under capital leases is stated at the present value of the minimum lease payments. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets. The estimated useful lives of property and equipment range from 1 to 10 years. Fixtures, which are comprised primarily of leasehold improvements and equipment under capital leases, are amortized on a straight-line basis over their estimated useful lives or for leasehold improvements, the related lease term, if less. The Company has capitalized certain internal use software and website development costs which are included in property and equipment. The estimated useful life of costs capitalized is evaluated for each specific project and ranges from 1 to 5 years. (m) Impairment or Disposal of Long-Lived Assets j2 Global accounts for long-lived assets, which include property and equipment and identifiable intangible assets with finite useful lives (subject to amortization), in accordance with the provisions of FASB ASC Topic No. 360, Property, Plant, and Equipment (“ASC 360”), which requires that long-lived assets be reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability is measured by comparing the carrying amount of an asset to the expected undiscounted future net cash flows generated by the asset. If it is determined that the asset may not be recoverable, and if the carrying amount of an asset exceeds its estimated fair value, an impairment charge is recognized to the extent of the difference. j2 Global assessed whether events or changes in circumstances have occurred that potentially indicate the carrying amount of long-lived assets may not be recoverable. No impairment was recorded in fiscal year 2017, 2016 or 2015. The Company classifies its long-lived assets to be sold as held for sale in the period (i) it has approved and committed to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and other actions required to sell the asset have been initiated, (iv) the sale of the asset is probable, (v) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value, and (vi) it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The Company initially measures a long-lived asset that is classified as held for sale at the lower of its carrying value or fair value less any costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized on the sale of a long-lived asset until the date of sale. Upon designation as an asset held for sale, the Company stops recording depreciation expense on the asset. The Company assesses the fair value of a long-lived asset less any costs to sell at each reporting period and until the asset is no longer is classified as held for sale. (n) Goodwill and Intangible Assets Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in a business combination. Intangible assets resulting from the acquisitions of entities accounted for using the purchase method of accounting are recorded at the estimated fair value of the assets acquired. Identifiable intangible assets are comprised of purchased customer relationships, trademarks and trade names, developed technologies and other intangible assets. Intangible assets subject to amortization are amortized over the period of estimated economic benefit ranging from 1 to 20 years. In accordance with FASB ASC Topic No. 350, Intangibles - Goodwill and Other (“ASC 350”), goodwill and other intangible assets with indefinite lives are not amortized but tested annually for impairment or more frequently if j2 Global believes indicators of impairment exist. In connection with the annual impairment test for goodwill, the Company has the option to perform a qualitative assessment in determining whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If the Company determines that it was more likely than not that the fair value of the reporting unit is less than its carrying amount, then it performs the impairment test upon goodwill. The impairment test involves a two-step process. The first step involves comparing the fair values of the applicable reporting units with their aggregate carrying values, including goodwill. The Company generally determines the fair value of its reporting units using the income approach methodology of valuation. If the carrying value of a reporting unit exceeds the reporting unit’s fair value, j2 Global performs the second step of the test to determine the amount of impairment loss. The second step involves measuring the impairment by comparing the implied fair values of the affected reporting unit’s goodwill and intangible assets with the respective carrying values. In accordance with ASC 350, the Company performed the annual impairment test for goodwill for fiscal year 2017 using a qualitative assessment primarily taking into consideration macroeconomic, industry and market conditions, overall financial performance and any other relevant company-specific events. The Company performed the annual impairment test for intangible assets with indefinite lives for fiscal 2017 using a qualitative assessment primarily taking into consideration macroeconomic, industry and market conditions, overall financial performance and any other relevant company-specific events. j2 Global concluded that there were no impairments in 2017, 2016 and 2015. (o) Contingent Consideration j2 Global measures the contingent earn-out liabilities in connection with acquisitions at fair value on a recurring basis using significant unobservable inputs classified within Level 3 of the fair value hierarchy (see Note 6 - Fair Value Measurements). The Company may use various valuation techniques depending on the terms and conditions of the contingent consideration including a Monte-Carlo simulation. This simulation uses a probability distribution for each significant input to produce hundreds or thousands of possible outcomes and the results are analyzed to determine probabilities of different outcomes occurring. Significant increases or decreases to these inputs in isolation would result in a significantly higher or lower liability with a higher liability capped by the contractual maximum of the contingent earn-out obligation. Ultimately, the liability will be equivalent to the amount paid, and the difference between the fair value estimate and amount paid will be recorded in earnings. The amount paid that is less than or equal to the liability on the acquisition date is reflected as cash used in financing activities in our consolidated statements of cash flows. Any amount paid in excess of the liability on the acquisition date is reflected as cash used in operating activities. j2 Global reviews and re-assess the estimated fair value of contingent consideration on a quarterly basis, and the updated fair value could differ materially from the initial estimates. Changes in the estimated fair value of our contingent earn-out liabilities related to the time component of the present value calculation are reported in interest expense. Adjustments to the estimated fair value related to changes in all other unobservable inputs are reported in operating income. (p) Income Taxes j2 Global’s income is subject to taxation in both the U.S. and numerous foreign jurisdictions. Significant judgment is required in evaluating the Company’s tax positions and determining its provision for income taxes. During the ordinary course of business, there are many transactions and calculations for which the ultimate tax determination is uncertain. j2 Global establishes reserves for tax-related uncertainties based on estimates of whether, and the extent to which, additional taxes will be due. These reserves for tax contingencies are established when the Company believes that certain positions might be challenged despite the Company’s belief that its tax return positions are fully supportable. j2 Global adjusts these reserves in light of changing facts and circumstances, such as the outcome of a tax audit or lapse of a statute of limitations. The provision for income taxes includes the impact of reserve provisions and changes to reserves that are considered appropriate. j2 Global accounts for income taxes in accordance with FASB ASC Topic No. 740, Income Taxes (“ASC 740”), which requires that deferred tax assets and liabilities be recognized using enacted tax rates for the effect of temporary differences between the book and tax basis of recorded assets and liabilities. ASC 740 also requires that deferred tax assets be reduced by a valuation allowance if it is more likely than not that some or all of the net deferred tax assets will not be realized. The valuation allowance is reviewed quarterly based upon the facts and circumstances known at the time. In assessing this valuation allowance, j2 Global reviews historical and future expected operating results and other factors, including its recent cumulative earnings experience, expectations of future taxable income by taxing jurisdiction and the carryforward periods available for tax reporting purposes, to determine whether it is more likely than not that deferred tax assets are realizable. ASC 740 provides guidance on the minimum threshold that an uncertain income tax benefit is required to meet before it can be recognized in the financial statements and applies to all income tax positions taken by a company. ASC 740 contains a two-step approach to recognizing and measuring uncertain income tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon settlement. If it is not more likely than not that the benefit will be sustained on its technical merits, no benefit will be recorded. Uncertain income tax positions that relate only to timing of when an item is included on a tax return are considered to have met the recognition threshold. j2 Global recognized accrued interest and penalties related to uncertain income tax positions in income tax expense on its consolidated statements of income. (q) Share-Based Compensation j2 Global accounts for share-based awards in accordance with the provisions of FASB ASC Topic No. 718, Compensation - Stock Compensation (“ASC 718”). Accordingly, j2 Global measures share-based compensation expense at the grant date, based on the fair value of the award, and recognizes the expense over the employee’s requisite service period using the straight-line method. The measurement of share-based compensation expense is based on several criteria, including but not limited to the valuation model used and associated input factors, such as expected term of the award, stock price volatility, risk free interest rate, dividend rate and award cancellation rate. These inputs are subjective and are determined using management’s judgment. If differences arise between the assumptions used in determining share-based compensation expense and the actual factors, which become known over time, j2 Global may change the input factors used in determining future share-based compensation expense. Any such changes could materially impact the Company’s results of operations in the period in which the changes are made and in periods thereafter. The Company estimates the expected term based upon the historical exercise behavior of our employees. j2 Global accounts for option grants to non-employees in accordance with FASB ASC Topic No. 505, Equity, whereby the fair value of such options is determined using the Black-Scholes option pricing model at the earlier of the date at which the non-employee’s performance is complete or a performance commitment is reached. (r) Earnings Per Common Share (“EPS”) EPS is calculated pursuant to the two-class method as defined in ASC Topic No. 260, Earnings per Share (“ASC 260”), which specifies that all outstanding unvested share-based payment awards that contain rights to nonforfeitable dividends or dividend equivalents are considered participating securities and should be included in the computation of EPS pursuant to the two-class method. Basic EPS is calculated by dividing net distributed and undistributed earnings allocated to common shareholders, excluding participating securities, by the weighted-average number of common shares outstanding. The Company’s participating securities consist of its unvested share-based payment awards that contain rights to nonforfeitable dividends or dividend equivalents. Diluted EPS includes the determinants of basic EPS and, in addition, reflects the impact of other potentially dilutive shares outstanding during the period. The dilutive effect of participating securities is calculated under the more dilutive of either the treasury method or the two-class method. (s) Research, Development and Engineering Research, development and engineering costs are expensed as incurred. Costs for software development incurred subsequent to establishing technological feasibility, in the form of a working model, are capitalized and amortized over their estimated useful lives. (t) Segment Reporting FASB ASC Topic No. 280, Segment Reporting (“ASC 280”), establishes standards for the way that public business enterprises report information about operating segments in their annual consolidated financial statements and requires that those enterprises report selected information about operating segments in interim financial reports. ASC 280 also establishes standards for related disclosures about products and services, geographic areas and major customers. The Company operates as two segments: (1) Cloud Services and (2) Digital Media. (u) Advertising Costs Advertising costs are expensed as incurred. Advertising costs for the years ended December 31, 2017, 2016 and 2015 was $143.3 million , $96.8 million and $63.5 million , respectively. (v) Sales Taxes The Company may collect sales taxes from certain customers which are remitted to governmental authorities as required and are excluded from revenues. (w) Recent Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers, as a new Topic, Accounting Standards Codification (“ASC”) Topic 606. The new revenue recognition standard provides a five-step analysis of transactions to determine when and how revenue is recognized. The core principle is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers: Deferral of the Effective Date, which deferred the effective date of the new revenue standard for periods beginning after December 15, 2016 to December 15, 2017, with early adoption permitted but not earlier than the original effective date. In March 2016, the FASB issued ASU 2016-08, Revenue from Contracts with Customers (Topic 606). This ASU is related to reporting revenue gross versus net, or principal versus agent considerations. This ASU is meant to clarify the guidance in ASU 2014-09, Revenue from Contracts with Customers, as it pertains to principal versus agent considerations. Specifically, the guidance addresses how entities should identify goods and services being provided to a customer, the unit of account for a principal versus agent assessment, how to evaluate whether a good or service is controlled before being transferred to a customer, and how to assess whether an entity controls services performed by another party. In April 2016, the FASB issued ASU 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing. This ASU is meant to clarify the guidance in FASB ASU 2014-09, Revenue from Contracts with Customers. Specifically, the guidance addresses an entity’s identification of its performance obligations in a contract, as well as an entity’s evaluation of the nature of its promise to grant a license of intellectual property and whether or not that revenue is recognized over time or at a point in time. In May 2016, the FASB issued ASU 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients. This ASU does not change the core principle of the guidance in Topic 606. Instead, the amendments provide clarifying guidance in a few narrow areas and add some practical expedients. In December 2016, the FASB issued 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers. The amendments in this ASU represent changes to clarify the Codification or to correct unintended application of guidance. This ASU must be applied retrospectively to each period presented or as a cumulative-effect adjust

Business Acquisition

Business Acquisition	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Business Acquisition	Business Acquisitions The Company uses acquisitions as a strategy to grow its customer base by increasing its presence in new and existing markets, expand and diversify its service offerings, enhance its technology, acquire skilled personnel and enter into other jurisdictions. The Company completed the following acquisitions during the year ended December 31, 2017 , paying the purchase price in cash in each transaction: (a) an asset purchase of sFax, acquired on March 31, 2017, an Austin-based provider of mobile cloud faxing for health care; (b) a share purchase of the entire issued capital of WeCloud AB, acquired on June 12, 2017, a Swedish-based provider of cloud-based internet security services; (c) an asset purchase of MyPhoneFax.com, acquired on June 30, 2017, a provider of online fax services; (d) an asset purchase of EZ Publishing (dba “StreamSend”), acquired on August 22, 2017, a provider of email marketing solutions; (e) a share purchase of all the issued capital of Humble Bundle Inc., acquired on October 13, 2017, a digital storefront for video games based in California; (f) an asset purchase of blackfriday.com, acquired on November 7, 2017, an online solution that markets popular Black Friday ads that are centrally located connecting shoppers with retailers; (g) a share purchase of all the issued capital of OnTargetJobs, Inc., acquired on December 4, 2017, a provider of online recruitment solutions for job seekers and employers in North America; (h) a share purchase of all the issued capital of Mashable Inc., acquired on December 5, 2017, a global, multi-platform media and entertainment company providing tech, digital culture and entertainment content around the globe; and (i) other immaterial acquisitions of online data backup, email marketing and email security businesses. The consolidated statement of income since the date of each acquisition and balance sheet as of December 31, 2017 , reflect the results of operations of all 2017 acquisitions. For the year ended December 31, 2017 , these acquisitions contributed $34.7 million to the Company’s revenues. Net income contributed by these acquisitions was not separately identifiable due to j2 Global’s integration activities and is impracticable to provide. Total consideration for these transactions was $203.9 million , net of cash acquired and assumed liabilities and subject to certain post-closing adjustments which may increase or decrease the final consideration paid. The following table summarizes the allocation of the purchase consideration for all 2017 acquisitions (in thousands): Assets and Liabilities Valuation Accounts receivable $ 14,130 Other assets 10,243 Property and equipment 6,411 Deferred tax asset 405 Trade names 20,610 Trademarks 1,373 Customer relationships 61,307 Other intangibles 36,998 Goodwill 121,827 Accounts payables and accrued expenses (27,995 ) Deferred revenue (11,853 ) Deferred tax liability (29,534 ) Total $ 203,922 During 2017, the purchase price accounting has been finalized for the following acquisitions: (i) Fonebox; (ii) Everyday Health Inc.; (iii) sFax; (iv) MyPhoneFax.com; (v) StreamSend; and (vi) other immaterial fax, online data backup, email security and email marketing businesses. The initial accounting for all other 2017 acquisitions is incomplete and subject to change, which may be significant. j2 Global has recorded provisional amounts which may be based upon past acquisitions with similar attributes for certain intangible assets (including trade names, software and customer relationships), preliminary acquisition date working capital and related tax items. During the year ended December 31, 2017 , the Company recorded adjustments to prior period acquisitions due to the finalization of the purchase accounting in the Cloud Services segment which resulted in a net decrease in goodwill of $(0.8) million . In addition, the Company recorded adjustments to the initial working capital related to prior period acquisitions in the Digital Media segment, which resulted in a net decrease in goodwill of $(4.7) million (see Note 8 - Goodwill and Intangible Assets). Such adjustments had an immaterial impact to amortization expense within the Consolidated Statement of Income for the year ended December 31, 2017. Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired and represents intangible assets that do not qualify for separate recognition. Goodwill recognized in connection with these acquisitions during the year ended December 31, 2017 is $121.8 million , of which $34.7 million is expected to be deductible for income tax purposes. 2016 The Company completed the following acquisitions during the year ended December 31, 2016, paying the purchase price in cash for each transaction: (a) an asset purchase of VaultLogix, acquired on February 17, 2016, a Massachusetts-based provider of cloud data backup and storage for business clients; (b) a share purchase of the entire issued capital of Callstream Group Limited, acquired on March 3, 2016, a provider of cloud-based call management solutions to markets in the United Kingdom; (c) an asset purchase of Publicaster, acquired on April 1, 2016, a Maryland-based provider of email marketing services; (d) an asset purchase of SMTP, acquired on June 27, 2016, a Florida-based provider of cloud email services offering solutions ranging from sophisticated transactional email solutions to cost-effective Simple Mail Transfer Protocol (“SMTP”) relay services; (e) a share purchase of the entire issued capital of Integrated Global Concepts, Inc. (“IGC”), acquired on July 12, 2016, a Chicago-based provider of fax and voicemail services; (f) a share purchase of the entire issued capital of Front-safe A/S, acquired on July 15, 2016, a Denmark-based provider of cloud backup solutions; (g) an asset purchase of Fonebox Australia, acquired on October 18, 2016, an Australia-based provider of voice, call routing and virtual receptionist business; (h) a share purchase of all the outstanding shares of common stock of Everyday Health Inc. (“Everyday Health”), acquired on December 5, 2016, a New York-based provider of digital health and wellness solutions; and (i) other immaterial acquisitions of online data backup, email marketing, email security and digital media businesses. The consolidated statement of income since the date of each acquisition and balance sheet, as of December 31, 2016 , reflect the results of operations of all 2016 acquisitions. For the year ended December 31, 2016 , these acquisitions contributed $52.9 million to the Company’s revenues. Net income contributed by these acquisitions was not separately identifiable due to j2 Global’s integration activities and is impracticable to provide. Total consideration for these transactions was $596.1 million , net of cash acquired and assumed liabilities and subject to certain post-closing adjustments which may increase or decrease the final consideration paid. The following table summarizes the allocation of the purchase consideration for all 2016 acquisitions (in thousands): Assets and Liabilities (1) Valuation Accounts receivable $ 70,922 Other assets 11,730 Property and equipment 11,109 Trade names 5,866 Trademarks 70,300 Customer relationships 85,482 Other intangibles 91,264 Goodwill 333,190 Accounts payables and accrued expenses (62,188 ) Deferred revenue (6,904 ) Deferred tax liability (14,503 ) Capital lease (194 ) Total $ 596,074 (1) In connection with the purchase of IGC, the majority of the value was associated with the 935,231 shares of j2 Global common stock held by IGC. The value associated with these shares was recorded as a separate transaction from the fax business and has been excluded from the schedule above. During the year ended December 31, 2016, the Company recorded adjustments to prior period acquisitions primarily due to the finalization of the purchase accounting in the Cloud Services segment which resulted in a net increase in goodwill in the amount of $0.8 million . In addition, the Company recorded adjustments to the initial working capital related to prior period acquisitions and updated the purchase accounting of Offers.com in the Digital Media segment, which resulted in a net decrease in goodwill in the amount of $(5.0) million with a corresponding increase in trade names, net and other purchased intangibles, net (see Note 8 - Goodwill and Intangible Assets). Such adjustments had an immaterial impact to amortization expense within the Consolidated Statement of Income for the year ended December 31, 2016. Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired and represents intangible assets that do not qualify for separate recognition. Goodwill recognized in connection with these acquisitions during the year ended December 31, 2016 is $333.2 million , of which $102.4 million is expected to be deductible for income tax purposes. IGC The Company acquired the entire issued capital of IGC on July 12, 2016 for a cash purchase price of approximately $6.3 million (excluding amounts allocated to the Company’s purchase of its common stock described below), net of cash acquired and assumed liabilities and is subject to certain post-closing adjustments which may increase or decrease the final consideration paid. At the date of acquisition, IGC held 935,231 of the Company’s common stock which the Company determined should be treated as a separate transaction from the acquired fax and voicemail businesses. In order to determine the amount of purchase consideration allocable to the fax and voicemail business and the Company’s common stock, the Company used a relative fair value approach and concluded that the amounts of consideration allocable to the fax and voicemail business and the Company’s common stock were $6.3 million and $51.5 million , respectively. See Note 12 - Stockholders’ Equity for further discussion regarding the Company’s common stock acquired in connection with the IGC business combination. Everyday Health On December 5, 2016, the Company acquired all the outstanding shares of common stock of Everyday Health, $0.01 par value per share, at a purchase consideration $493.7 million (net of cash acquired and assumed liabilities) or $10.50 per share in cash, and subject to certain post-closing adjustments which may increase or decrease the final consideration paid. Everyday Health is a leading provider of digital health and marketing and communication solutions. Everyday Health attracts a large and engaged audience of consumers and healthcare professionals to its premier health and wellness properties and utilizes its data and analytics expertise to deliver highly personalized content experiences and efficient and effective marketing and engagement solutions. Everyday Health enables consumers to manage their daily health and wellness needs, healthcare professionals to stay informed and make better decisions for their patients, and marketers, health payers and providers to communicate and engage with consumers and healthcare professionals to drive better health outcomes. Everyday Health’s content and solutions are delivered through multiple channels, including desktop, mobile web, mobile phone and tablet applications, as well as video and social media. The Company acquired Everyday Health to bring together two leading digital media companies with complimentary visions and platforms to engage and monetize audiences. The combined company will be well positioned to deliver compelling benefits to customers with content that connects, informs and empowers audiences. The Company’s Digital Media segment maintains leading positions in the technology, gaming and men's lifestyle verticals with strong and well-established brands. Everyday Health adds a new vertical and set of market-leading trusted health properties to the portfolio while diversifying the company’s audience mix. The consolidated statement of income, since the date of acquisition, and balance sheet, as of December 31, 2016 , reflect the results of operations Everyday Health. For the year ended December 31, 2016 , Everyday Health contributed $23.2 million to the Company’s revenues. Net income contributed by Everyday Health was not separately identifiable due to j2 Global’s integration activities and is impracticable to provide. The following table summarizes the allocation of the purchase consideration for the Everyday Health acquisition (in thousands): Assets and Liabilities Valuation Cash $ 15,918 Accounts receivable 67,968 Other assets 11,168 Property and equipment 6,494 Trademarks 70,300 Customer relationships 45,500 Other intangibles 88,267 Goodwill 263,988 Accounts payables and accrued expenses (59,091 ) Deferred revenue (5,297 ) Deferred tax liability (11,500 ) Total $ 493,715 Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired and represents intangible assets that do not qualify for separate recognition. Goodwill recognized in connection with the Everyday Health acquisition during the year ended December 31, 2016 is $264.0 million , of which $65.4 million is expected to be deductible for income tax purposes. Pro Forma Financial Information for Everyday Health Acquisition The following unaudited pro forma supplemental information is based on estimates and assumptions, which j2 Global believes are reasonable. However, this information is not necessarily indicative of the Company’s consolidated financial position or results of income in future periods or the results that actually would have been realized had j2 Global and Everyday Health been combined companies during the periods presented. These pro forma results exclude any savings or synergies that would have resulted from the Everyday Health business acquisition had it occurred on January 1, 2015 and do not take into consideration the exiting of any acquired lines of business. This unaudited pro forma supplemental information includes incremental intangible asset amortization and other charges as a result of the Everyday Health acquisition, net of the related tax effects. The supplemental information on an unaudited pro forma financial basis presents the combined results of j2 Global and Everyday Health as if the acquisition had occurred on January 1, 2015 (in thousands, except per share amounts): Year ended December 31, 2016 December 31, 2015 (unaudited) (unaudited) Revenues $ 1,082,813 $ 952,806 Net income $ 103,541 $ 115,059 EPS - Basic $ 2.14 $ 2.38 EPS - Diluted $ 2.13 $ 2.35 Pro Forma Financial Information for All 2016 Acquisitions The following unaudited pro forma supplemental information is based on estimates and assumptions, that j2 Global believes are reasonable. However, this information is not necessarily indicative of the Company’s consolidated financial position or results of income in future periods or the results that actually would have been realized had j2 Global and the acquired businesses been combined companies during the periods presented. These pro forma results exclude any savings or synergies that would have resulted from these business acquisitions had they occurred on January 1, 2015 and do not take into consideration the exiting of any acquired lines of business. This unaudited pro forma supplemental information includes incremental intangible asset amortization and other charges as a result of the acquisitions, net of the related tax effects. The supplemental information on an unaudited pro forma financial basis presents the combined results of j2 Global and its 2016 acquisitions as if each acquisition had occurred on January 1, 2015 (in thousands, except per share amounts): Year ended December 31, 2016 December 31, 2015 (unaudited) (unaudited) Revenues $ 1,102,510 $ 1,009,169 Net income $ 108,822 $ 111,817 EPS - Basic $ 2.25 $ 2.31 EPS - Diluted $ 2.24 $ 2.29 2015 The Company completed the following acquisitions during the year ended December 31, 2015, paying the purchase price in cash for each transaction: (a) a share purchase of the entire issued share capital of Firstway, acquired on February 11, 2015, an Ireland-based distributor of FaxBOX® digital fax services; (b) an asset purchase of Nuvotera (formerly known as Spam Soap), acquired on February 13, 2015, a California-based supplier of email security; (c) an asset purchase of EmailDirect, acquired on February 19, 2015, a California-based provider of email marketing services; (d) an asset purchase of SugarSync®, Inc., acquired on March 23, 2015, a California-based provider of online file backup, synchronization and sharing assets; (e) an asset purchase of Popfax, acquired on September 23, 2015, a France-based global provider of internet fax services; (f) a stock purchase of the entire capital stock of Salesify, acquired on September 17, 2015, a California-based based provider of lead generation solutions; (g) an asset purchase of LiveVault®, acquired on September 30, 2015, a California-based global provider of data backup and recovery services; (h) a membership interest purchase of the entire units of Offers.com, acquired on December 31, 2015, a Texas-based and is an online marketplace connecting millions of consumers with discounts from thousands of leading merchants; and (i) certain other immaterial acquisitions of fax, online data backup and email businesses. The consolidated statement of income since the date of each acquisition and balance sheet, as of December 31, 2015, reflect the results of operations of all 2015 acquisitions. For the year ended December 31, 2015, these acquisitions contributed $52.4 million to the Company’s revenues. Net income contributed by these acquisitions was not separately identifiable due to j2 Global’s integration activities. Total consideration for these transactions was $314.0 million , net of cash acquired and assumed liabilities and subject to certain post-closing adjustments. The following table summarizes the allocation of the purchase consideration as follows (in thousands): Assets and Liabilities Valuation Accounts receivable $ 14,935 Other assets 1,415 Property and equipment 5,769 Software 18,764 Trade names 22,602 Customer relationships 98,027 Other intangibles 1,873 Goodwill 172,593 Accounts payables and accrued expenses (9,684 ) Deferred revenue (10,764 ) Deferred tax liability (1,316 ) Capital lease (195 ) Total $ 314,019 Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired and represents intangible assets that do not qualify for separate recognition. Goodwill recognized in connection with these acquisitions during the year ended December 31, 2015 is $172.6 million , of which $143.3 million is expected to be deductible for income tax purposes. Pro Forma Financial Information for 2015 Acquisitions The following unaudited pro forma supplemental information is based on estimates and assumptions that j2 Global believes are reasonable. However, this information is not necessarily indicative of the Company’s consolidated financial position or results of income in future periods or the results that actually would have been realized had j2 Global and the acquired businesses been combined companies during the period presented. These pro forma results exclude any savings or synergies that would have resulted from these business acquisitions had they occurred on January 1, 2014 and do not take into consideration the exiting of any acquired lines of business. This unaudited pro forma supplemental information includes incremental intangible asset amortization and other charges as a result of the acquisitions, net of the related tax effects. The supplemental information on an unaudited pro forma financial basis presents the combined results of j2 Global and its 2015 acquisitions as if each acquisition had occurred on January 1, 2014 (in thousands, except per share amounts): Year ended December 31, 2015 December 31, 2014 (unaudited) (unaudited) Revenues $ 823,904 $ 744,388 Net income $ 159,408 $ 126,196 EPS - Basic $ 3.29 $ 2.64 EPS - Diluted $ 3.26 $ 2.62

Investments

Investments	12 Months Ended
	Dec. 31, 2017
Investments [Abstract]
Investments	Investments Investments consist of certificates of deposits and equity securities. The Company’s equity investments were received as part of the consideration for the sale of Tea Leaves Health, LLC (“Tea Leaves”) which occurred on October 5, 2017 and are without readily determinable fair values because these securities are privately held, not traded on any public exchanges and is not an investment in any mutual fund or similar type investment. As a result, the Company has determined that these investments should be accounted for using the cost method of accounting in accordance with FASB ASC Topic 325, Investments - Other (see Note 5 - Assets Held for Sale). The following table summarizes the Company’s investments (in thousands): December 31, December 31, 2016 Certificates of deposit $ — $ 60 Equity securities 57,722 — Total $ 57,722 $ 60 For the years ended December 31, 2017 , 2016 and 2015 , the Company recorded realized gains from the sale of investments of approximately zero , $7.7 million and $0.5 million , respectively. During the years ended December 31, 2017 , 2016 and 2015, we did not recognize any other-than-temporary impairment losses.

Assets Held for Sale (Notes)

Assets Held for Sale (Notes)	12 Months Ended
	Dec. 31, 2017
Assets held for sale [Abstract]
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]	Assets Held for Sale During the second quarter 2017, the Company committed to a plan to sell Cambridge BioMarketing Group, LLC (“Cambridge”), a subsidiary within the Digital Media segment, as it was determined to be a non-core asset. On July 12, 2017, in a cash transaction, the Company sold Cambridge for a loss of $0.9 million which was recorded in other (income) expense, net. During the third quarter 2017, the Company committed to a plan to sell j2 Australia Hosting Pty Ltd (dba “Web24”), a subsidiary within the Cloud Services segment, as it was determined to be a non-core asset. On September 1, 2017, in a cash transaction, the Company sold Web24 for a gain of $1.6 million which was recorded in other (income) expense, net. During the third quarter 2017, the Company committed to a plan to sell Tea Leaves, a subsidiary within the Digital Media segment, as it was determined to be a non-core asset. On October 5, 2017, in a transaction consisting of a combination of cash and various equity securities, the Company sold Tea Leaves for a gain of $27.0 million which was recorded in other (income) expense, net.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements j2 Global complies with the provisions of ASC 820, which defines fair value, provides a framework for measuring fair value and expands the disclosures required for fair value measurements of financial and non-financial assets and liabilities. ASC 820 clarifies that fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that is determined based on assumptions that market participants would use in pricing an asset or a liability. As a basis for considering such assumptions, ASC 820 establishes a three-tier value hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value: § Level 1 – Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. § Level 2 – Observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. § Level 3 – Unobservable inputs which are supported by little or no market activity. The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The Company’s money market funds are classified within Level 1. The Company values these Level 1 investments using quoted market prices. The fair value of the Convertible Notes (see Note 9 - Long-Term Debt) is determined using recent quoted market prices or dealer quotes for such securities, which are Level 1 inputs. The fair value of our senior notes (8.0% senior unsecured notes at December 31, 2016 and 6.0% senior unsecured notes at December 31, 2017 ) (see Note 9 - Long-Term Debt) is determined using quoted market prices or dealer quotes for instruments with similar maturities and other terms and credit ratings, which are Level 2 inputs. The fair value of long-term debt was $1.2 billion and $792.2 million , at December 31, 2017 and December 31, 2016 , respectively. In addition, the Convertible Notes contain terms that may require the Company to pay contingent interest on the Convertible Notes which is accounted for as a derivative with fair value adjustments being recorded to interest expense (see Note 9 - Long Term Debt). This derivative is fair valued using a binomial lattice convertible bond pricing model using historical and implied market information, which are Level 2 inputs. The Company classifies its contingent consideration liability in connection with acquisitions within Level 3 because factors used to develop the estimated fair value are unobservable inputs, such as volatility and market risks, and are not supported by market activity. The fair value of the contingent consideration liability was determined using option based approaches. This methodology was utilized because the distribution of payments is not symmetric and amounts are only payable upon certain earnings before interest, tax, depreciation and amortization (“EBITDA”) thresholds being reached. Such valuation approach included a Monte-Carlo simulation for the contingency since the financial metric driving the payments is path dependent. Significant increases or decreases in either of the inputs noted above in isolation would result in a significantly lower or higher fair value measurement. The following tables present the fair values of the Company’s financial assets or liabilities that are measured at fair value on a recurring basis (in thousands): December 31, 2017 Level 1 Level 2 Level 3 Fair Value Assets: Cash equivalents: Money market and other funds $ 453 $ — $ — $ 453 Total assets measured at fair value $ 453 $ — $ — $ 453 Liabilities: Contingent consideration $ — $ — $ 20,477 $ 20,477 Contingent interest derivative — 768 — 768 Total liabilities measured at fair value $ — $ 768 $ 20,477 $ 21,245 December 31, 2016 Level 1 Level 2 Level 3 Fair Value Assets: Cash equivalents: Money market and other funds $ 7,737 $ — $ — $ 7,737 Certificates of Deposit — 60 — 60 Total assets measured at fair value $ 7,737 $ 60 $ — $ 7,797 Liabilities: Contingent consideration $ — $ — $ 17,450 $ 17,450 Contingent interest derivative — 958 — 958 Total liabilities measured at fair value $ — $ 958 $ 17,450 $ 18,408 At the end of each reporting period, management reviews the inputs to measure the fair value measurements of financial and non-financial assets and liabilities to determine when transfers between levels are deemed to have occurred. For the years ended December 31, 2017 and 2016, there were no transfers that have occurred between levels. The following table presents a reconciliation of the Company’s derivative instruments (in thousands): Amount Affected line item in the Statement of Income Derivative Liabilities: Level 2: Balance as of January 1, 2016 $ 1,450 Total fair value adjustments reported in earnings (492 ) Interest expense, net Balance as of December 31, 2016 $ 958 Total fair value adjustments reported in earnings (190 ) Interest expense, net Balance as of December 31, 2017 $ 768 The following tables presents a reconciliation of the Company’s Level 3 financial assets or liabilities that are measured at fair value on a recurring basis (in thousands): Level 3 Affected line item in the Statement of Income Balance as of January 1, 2016 $ 30,600 Total fair value adjustments reported in earnings 4,850 General and administrative Contingent consideration payments (18,000 ) Not Applicable Balance as of December 31, 2016 $ 17,450 Contingent consideration 17,577 Total fair value adjustments reported in earnings 2,300 General and administrative Contingent consideration payments (16,850 ) Not Applicable Balance as of December 31, 2017 $ 20,477 In connection with the acquisition of Ookla on December 1, 2014, contingent consideration of up to an aggregate of $40.0 million may be payable upon achieving certain future income thresholds and had a fair value of $17.0 million at December 31, 2016. Due to the Company achieving certain earnings targets for the year ended December 31, 2016, $20.0 million ( $16.9 million of contingent consideration and $3.1 million of compensation) was paid during the second quarter of 2017. There are no further payments pending. In connection with the acquisition of Salesify on September 17, 2015, contingent consideration of up to an aggregate of $17.0 million may be payable upon achieving certain future income thresholds and had a fair value of zero and $0.6 million at December 31, 2017 and 2016, respectively. In connection with the acquisition of Humble Bundle, on October 13, 2017, contingent consideration of up to an aggregate of $40.0 million may be payable upon achieving certain future income thresholds and had a fair value of $19.7 million at December 31, 2017 which was recorded as an other long-term liability on the consolidated balance sheet at December 31, 2017 . In connection with the acquisition of blackfriday.com on November 7, 2017, contingent consideration of up to an aggregate of $1.5 million may be payable upon achieving certain future income thresholds and had a fair value of $0.8 million at December 31, 2017 which was recorded as an other long-term liability on the consolidated balance sheet at December 31, 2017 . During the year ended December 31, 2017 , the Company recorded a net increase in the fair value of the contingent consideration of $2.3 million and reported such increase in general and administrative expenses.

Property And Equipment

Property And Equipment	12 Months Ended
	Dec. 31, 2017
Property And Equipment [Abstract]
Property And Equipment	Property and Equipment Property and equipment, stated at cost, at December 31, 2017 and 2016 consisted of the following (in thousands): 2017 2016 Computers and related equipment $ 215,631 $ 173,103 Furniture and equipment 2,035 1,928 Leasehold improvements 16,163 12,929 233,829 187,960 Less: Accumulated depreciation and amortization (154,056 ) (119,866 ) Total property and equipment, net $ 79,773 $ 68,094 Depreciation and amortization expense was $33.0 million , $26.8 million and $19.2 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. Total disposals of long-lived assets for the years ended December 31, 2017 , 2016 and 2015 was $4.0 million , zero and zero , respectively. The disposals during 2017 were primarily related to the sale of Cambridge, Web24, and Tea Leaves (see Note 5 - Assets Held for Sale).

Goodwill And Intangible Assets

Goodwill And Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill And Intangible Assets	Goodwill and Intangible Assets Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in a business combination. Intangible assets resulting from the acquisitions of entities accounted for using the purchase method of accounting are recorded at the estimated fair value of the assets acquired. Identifiable intangible assets are comprised of purchased customer relationships, trademarks and trade names, developed technologies and other intangible assets. The fair values of these identified intangible assets are based upon expected future cash flows or income, which take into consideration certain assumptions such as customer turnover, trade names and patent lives. These determinations are primarily based upon the Company’s historical experience and expected benefit of each intangible asset. If it is determined that such assumptions are not accurate, then the resulting change will impact the fair value of the intangible asset. Identifiable intangible assets are amortized over the period of estimated economic benefit, which ranges from one to 20 years. The changes in carrying amounts of goodwill for the years ended December 31, 2017 and 2016 are as follows (in thousands): Cloud Services Digital Media Consolidated Balance as of January 1, 2016 $ 502,718 $ 304,943 $ 807,661 Goodwill acquired (Note 3) 69,202 263,988 333,190 Purchase Accounting Adjustments (4) 816 (4,957 ) (4,141 ) Foreign exchange translation (13,584 ) (316 ) (13,900 ) Balance as of December 31, 2016 $ 559,152 $ 563,658 $ 1,122,810 Goodwill acquired (Note 3) 34,035 87,792 121,827 Goodwill written off related to sale of a business unit (1)(2)(3) (3,614 ) (54,127 ) (57,741 ) Purchase accounting adjustments (4) (766 ) (4,667 ) (5,433 ) Foreign exchange translation 14,946 202 15,148 Balance as of December 31, 2017 $ 603,753 $ 592,858 $ 1,196,611 (1) On July 12, 2017, in a cash transaction, the Company sold Cambridge which resulted in $17.8 million of goodwill being written off in connection with this sale (see Note 5 - Assets Held for Sale). (2) On September 1, 2017, in a cash transaction, the Company sold Web24 which resulted in $3.6 million of goodwill being written off in connection with this sale (see Note 5 - Assets Held for Sale). (3) On October 5, 2017, in a cash and equity transaction, the Company sold Tea Leaves, which resulted in $36.3 million of goodwill being written off in connection with this sale (see Note 5 - Assets Held for Sale). (4) Purchase accounting adjustments relate to adjustments to goodwill in connection with prior year business acquisitions (see Note 3 - Business Acquisitions). Intangible assets are summarized as of December 31, 2017 and 2016 as follows (in thousands): Intangible Assets with Indefinite Lives: 2017 2016 Trade names $ 27,379 $ 27,379 Other 5,432 5,432 Total $ 32,811 $ 32,811 Intangible Assets Subject to Amortization: As of December 31, 2017 , intangible assets subject to amortization relate primarily to the following (in thousands): Weighted-Average Amortization Period Historical Cost Accumulated Amortization Net Trade names 11.2 years $ 147,997 $ 51,429 $ 96,568 Patent and patent licenses 6.6 years 67,724 56,853 10,871 Customer relationships (1) 8.9 years 447,070 253,464 193,606 Other purchased intangibles 4.8 years 218,628 66,733 151,895 Total $ 881,419 $ 428,479 $ 452,940 (1) Historically, the Company has amortized its customer relationship assets in a pattern that best reflects the pace in which the assets’ benefits are consumed. This pattern results in a substantial majority of the amortization expense being recognized in the first four to five years, despite the overall life of the asset. As of December 31, 2016 , intangible assets subject to amortization relate primarily to the following (in thousands): Weighted-Average Amortization Period Historical Cost Accumulated Amortization Net Trade names 11.5 years $ 127,342 $ 38,868 $ 88,474 Patent and patent licenses 6.6 years 65,605 51,677 13,928 Customer relationships (1) 9.6 years 390,930 182,775 208,155 Other purchased intangibles 6.0 years 195,913 27,590 168,323 Total $ 779,790 $ 300,910 $ 478,880 (1) Historically, the Company has amortized its customer relationship assets in a pattern that best reflects the pace in which the assets’ benefits are consumed. This pattern results in a substantial majority of the amortization expense being recognized in the first four to five years, despite the overall life of the asset. During the year ended December 31, 2016 , the Company acquired Everyday Health. The identified intangible assets recognized as part of the acquisition and their respective estimated weighted average amortizations were as follows (in thousands): December 31, 2016 Weighted-Average Amortization Period Fair Value Trademarks 5.2 years $ 70,300 Customer relationships 10.1 years 45,500 Other purchased intangibles 1.7 years 88,267 Total $ 204,067 During the year ended December 31, 2016 , the Company completed 21 other acquisitions which were individually immaterial. The identified intangible assets recognized as part of these acquisition and their respective estimated weighted average amortizations were as follows (in thousands): December 31, 2016 Weighted-Average Amortization Period Fair Value Trade names 6.3 years $ 5,866 Customer relationships 7.5 years 39,982 Other purchased intangibles 3.3 years 2,997 Total $ 48,845 Expected amortization expenses for intangible assets subject to amortization at December 31, 2017 are as follows (in thousands): Fiscal Year: 2018 $ 122,294 2019 103,172 2020 54,315 2021 35,280 2022 30,231 Thereafter 107,648 Total expected amortization expense $ 452,940 Amortization expense was $129.0 million , $95.3 million and $74.0 million for the years ended December 31, 2017 , 2016 and 2015 , respectively.

Long Term Debt

Long Term Debt	12 Months Ended
	Dec. 31, 2017
Long-term Debt, Unclassified [Abstract]
Debt Disclosure [Text Block]	Long-Term Debt 6.0% Senior Notes On June 27, 2017 , j2 Cloud Services, LLC (“j2 Cloud”) and j2 Cloud Co-Obligor, Inc. (the “Co-Issuer” and together with j2 Cloud, the “Issuers”), wholly-owned subsidiaries of the Company, completed the issuance and sale of $650 million aggregate principal amount of their 6.0% senior notes due in 2025 (the “6.0% Senior Notes”) in a private placement offering exempt from the registration requirements of the Securities Act of 1933. j2 Cloud received proceeds of $636.5 million , after deducting the initial purchasers’ discounts, commissions and offering expenses. The 6.0% Senior Notes are presented as long-term debt, net of deferred issuance costs, on the condensed consolidated balance sheets as of December 31, 2017 . The proceeds were used to redeem all of j2 Cloud’s 8.0% notes due in 2020, and to distribute sufficient net proceeds to j2 Global to pay off all amounts outstanding under its existing credit facility, with the remaining net proceeds to be used for general corporate purposes, including acquisitions. The 6.0% Senior Notes bear interest at a rate of 6.0% per annum, payable semi-annually in arrears on January 15 and July 15 of each year, commencing on January 15, 2018. The 6.0% Senior Notes mature on July 15, 2025 , and are senior unsecured obligations of the Issuers which are guaranteed on an unsecured basis by certain subsidiaries of j2 Cloud (as defined in the Indenture, dated June 27, 2017 (the “Indenture”)). If j2 Cloud or any of its restricted subsidiaries acquires or creates a domestic restricted subsidiary, other than an insignificant subsidiary (as defined in the Indenture), after the issue date, or any insignificant subsidiary ceases to fit within the definition of insignificant subsidiary, such restricted subsidiary is required to unconditionally guarantee, jointly and severally, on an unsecured basis, the Issuers’ obligations under the 6.0% Senior Notes. The Issuers may redeem some or all of the 6.0% Senior Notes at any time on or after July 15, 2020 at specified redemption prices plus accrued and unpaid interest, if any, to, but excluding the redemption date. Before July 15, 2020, in connection with certain equity offerings, the Issuers also may redeem up to 35% of the 6.0% Senior Notes at a price equal to 106.0% of the principal amount, plus accrued and unpaid interest, if any, to, but excluding the redemption date. In addition, at any time prior to July 15, 2020, the Issuers may redeem some or all of the 6.0% Senior Notes at a price equal to 100% of the principal amount, plus accrued and unpaid interest, if any, to the redemption date, plus an applicable “make-whole” premium. The indenture contains certain restrictive and other covenants applicable to j2 Cloud and subsidiaries designated as restricted subsidiaries including, but not limited to, restrictions on (i) paying dividends or making distributions on j2 Cloud’s membership interests or repurchasing j2 Cloud’s membership interests; (ii) making certain restricted payments; (iii) creating liens or entering into sale and leaseback transactions; (iv) entering into transactions with affiliates; (v) merging or consolidating with another company; and (vi) transferring and selling assets. These covenants include certain exceptions. Violation of these covenants could result in a default which could result in the acceleration of outstanding amounts if such default is not cured or waived within the time periods outlined in the indenture. Payments, specifically dividend payments, are restricted only if j2 Cloud and its subsidiaries designated as restricted subsidiaries have a leverage ratio of greater than 3.0 to 1.0. In addition, if such leverage ratio is in excess of 3.0 to 1.0, restriction on restricted payments is subject to various exceptions, including an exception for the payment of restricted payments up to $75 million. These contractual provisions did not, as of December 31, 2017 , restrict j2 Cloud’s ability to pay dividends to j2 Global, Inc. The Company is in compliance with its debt covenants as of December 31, 2017 . As of December 31, 2017 , the estimated fair value of the 6.0% Senior Notes was approximately $684.1 million and was based on the quoted market prices of debt instruments with similar terms, credit rating and maturities of the 6.0% Senior Notes which are Level 2 inputs (see Note 6 - Fair Value Measurements). 8.0% Senior Notes On August 1, 2017, j2 Cloud redeemed all of its outstanding $250 million 8.0% senior unsecured notes due in 2020 for $265 million , including a redemption premium and relevant accrued interest which resulted in a loss on extinguishment of $8.0 million recorded which was recorded in Interest expense, net. 3.25% Convertible Notes On June 10, 2014 , j2 Global issued $402.5 million aggregate principal amount of 3.25% convertible senior notes due June 15, 2029 (the “Convertible Notes”). j2 Global received proceeds of $391.4 million in cash, net of underwriters’ discounts and commissions. The net proceeds were available for general corporate purposes. The Convertible Notes bear interest at a rate of 3.25% per annum, payable semiannually in arrears on June 15 and December 15 of each year. Beginning with the six-month interest period commencing on June 15, 2021, the Company must pay contingent interest on the Convertible Notes during any six-month interest period if the trading price per $1,000 principal amount of the Convertible Notes for each of the five trading days immediately preceding the first day of such interest period equals or exceeds $1,300. Any contingent interest payable on the Convertible Notes will be in addition to the regular interest payable on the Convertible Notes. Holders may surrender their Convertible Notes for conversion at any time prior to the close of business on the business day immediately preceding the maturity date only if one or more of the following conditions is satisfied: (i) during any calendar quarter commencing after the calendar quarter ending on September 30, 2014 (and only during such calendar quarter), if the closing sale price of j2 Global common stock for at least 20 trading days in the period of 30 consecutive trading days ending on the last trading day of the calendar quarter immediately preceding the calendar quarter in which the conversion occurs is more than 130% of the applicable conversion price of the Convertible Notes on each such trading day; (ii) during the five consecutive business day period following any ten consecutive trading day period in which the trading price for the Convertible Notes for each such trading day was less than 98% of the product of (a) the closing sale price of j2 Global common stock on each such trading day and (b) the applicable conversion rate on each such trading day; (iii) if j2 Global calls any or all of the Convertible Notes for redemption, at any time prior to the close of business on the business day prior to the redemption date; (iv) upon the occurrence of specified corporate events; or (v) during either the period beginning on, and including, March 15, 2021 and ending on, but excluding, June 20, 2021 or the period beginning on, and including, March 15, 2029 and ending on, but excluding, the maturity date. j2 Global will settle conversions of Convertible Notes by paying or delivering, as the case may be, cash, shares of j2 Global common stock or a combination thereof at j2 Global’s election. The Company currently intends to satisfy its conversion obligation by paying and delivering a combination of cash and shares of the Company’s common stock, where cash will be used to settle each $1,000 of principal and the remainder, if any, will be settled via shares of the Company’s common stock. As of December 31, 2017, the conversion rate is 14.5899 shares of j2 Global common stock for each $1,000 principal amount of Convertible Notes, which represents a conversion price of approximately $68.54 per share of j2 Global common stock. The conversion rate is subject to adjustment for certain events as set forth in the indenture governing the Convertible Notes, but will not be adjusted for accrued interest. In addition, following certain corporate events that occur on or prior to June 20, 2021, j2 Global will increase the conversion rate for a holder that elects to convert its Convertible Notes in connection with such a corporate event. j2 Global may not redeem the Convertible Notes prior to June 20, 2021. On or after June 20, 2021, j2 Global may redeem for cash all or part of the Convertible Notes at a redemption price equal to 100% of the principal amount of the Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. No sinking fund is provided for the Convertible Notes. Holders have the right to require j2 Global to repurchase for cash all or part of their Convertible Notes on each of June 15, 2021 and June 15, 2024 at a repurchase price equal to 100% of the principal amount of the Convertible Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the relevant repurchase date. In addition, if a fundamental change, as defined in the indenture governing the Convertible Notes, occurs prior to the maturity date, holders may require j2 Global to repurchase for cash all or part of their Convertible Notes at a repurchase price equal to 100% of the principal amount of the Convertible Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. The Convertible Notes are the Company’s general senior unsecured obligations and rank: (i) senior in right of payment to any of the Company’s future indebtedness that is expressly subordinated in right of payment to the Convertible Notes; (ii) equal in right of payment to the Company’s existing and future unsecured indebtedness that is not so subordinated; (iii) effectively junior in right of payment to any of the Company’s secured indebtedness to the extent of the value of the assets securing such indebtedness; and (iv) structurally junior to all existing and future indebtedness (including trade payables) incurred by the Company’s subsidiaries. Accounting for the Convertible Notes In accordance with ASC 470-20, Debt with Conversion and Other Options, convertible debt that can be settled for cash is required to be separated into the liability and equity component at issuance, with each component assigned a value. The value assigned to the liability component is the estimated fair value, as of the issuance date, of similar debt without the conversion feature. The difference between the cash proceeds and estimated fair value of the liability component, representing the value of the conversion premium assigned to the equity component, is recorded as a debt discount on the issuance date. This debt discount is amortized to interest expense using the effective interest method over the period from the issuance date through the first stated repurchase date on June 15, 2021. j2 Global estimated the borrowing rates of similar debt without the conversion feature at origination to be 5.79% for the Convertible Notes and determined the debt discount to be $59.0 million . As a result, a conversion premium after tax of $37.7 million was recorded in additional paid-in capital. The aggregate debt discount is amortized as interest expense over the period from the issuance date through the first stated repurchase date on June 15, 2021 which management believes is the expected life of the Convertible Notes using an interest rate of 5.81% . As of December 31, 2017 , the remaining period over which the unamortized debt discount will be amortized is 3.5 years . The Convertible Notes are carried at face value less any unamortized debt discount. The fair value of the Convertible Notes at each balance sheet date is determined based on recent quoted market prices or dealer quotes for the Convertible Notes, which are Level 1 inputs (see Note 6 - Fair Value Measurements). If such information is not available, the fair value is determined using cash-flow models of the scheduled payments discounted at market interest rates for comparable debt without the conversion feature. As of December 31, 2017 and 2016, the estimated fair value of the Convertible Notes was approximately $504.5 million and $516.8 million , respectively. As of December 31, 2017 and 2016, the if-converted value of our Convertible Notes exceeded the principal amount of $402.5 million by $38.1 million and $75.2 million , respectively. The following table provides additional information related to our Convertible Notes (in thousands): 2017 2016 Additional paid-in capital $ 37,700 $ 37,700 Principal amount of Convertible Notes $ 402,500 $ 402,500 Unamortized discount of the liability component 32,189 40,356 Carrying amount of debt issuance costs 5,667 7,002 Net carrying amount of Convertible Notes $ 364,644 $ 355,142 The following table provides the components of interest expense related to our Convertible Notes (in thousands): 2017 2016 2015 Cash interest expense (coupon interest expense) $ 13,081 $ 13,081 $ 13,081 Non-cash amortization of discount on Convertible Notes 8,167 7,707 7,274 Amortization of debt issuance costs 1,335 1,217 1,109 Total interest expense related to Convertible Notes $ 22,583 $ 22,005 $ 21,464 The Company has recorded additional interest expense associated with the contingent interest feature of the Convertible Notes for the years ended December 31, 2017 , 2016 , and 2015 of $(0.2) million , $(0.5) million , and $0.7 million , respectively (see Note 6 - Fair Value Measurements). Long-term debt as of December 31, 2017 and 2016 consists of the following (in thousands): 2017 2016 Senior Notes: 6.0% Senior Notes $ 650,000 $ — 8.0% Senior Notes — 250,000 3.25% Convertible Notes 402,500 402,500 Less: Unamortized discount (42,902 ) (42,997 ) Deferred issuance costs (7,654 ) (7,757 ) Total long-term debt $ 1,001,944 $ 601,746 Less: Current portion — — Total long-term debt, less current portion $ 1,001,944 $ 601,746 At December 31, 2017 , future principal payments for debt were as follows (in thousands): Years Ended December 31, 2018 $ — 2019 — 2020 — 2021 402,500 2022 — Thereafter 650,000 $ 1,052,500 Interest expense was $59.2 million , $42.7 million and $43.6 million for the years ended December 31, 2017 , 2016 and 2015 , respectively.

Commitments And Contingencies

Commitments And Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	Commitments and Contingencies Litigation From time to time, j2 Global and its affiliates are involved in litigation and other legal disputes or regulatory inquiries that arise in the ordinary course of business. Any claims or regulatory actions against j2 Global and its affiliates, whether meritorious or not, could be time consuming and costly, and could divert significant operational resources. The outcomes of such matters are subject to inherent uncertainties, carrying the potential for unfavorable rulings that could include monetary damages and injunctive relief. On February 17, 2011, Emmanuel Pantelakis (“Pantelakis”) filed suit against a j2 Global affiliate in the Ontario Superior Court of Justice (No. 11-50673), alleging that the j2 Global affiliate breached a contract relating to Pantelakis’s use of the Campaigner ® service. The j2 Global affiliate filed a responsive pleading on March 23, 2011 and responses to undertakings on July 16, 2012. On November 6, 2012, Pantelakis filed a second amended statement of claim, reframing his lawsuit as a negligence action. The j2 Global affiliate filed an amended statement of defense on April 8, 2013. Discovery has closed. A judicial pre-trial has been set for July 27, 2018. On January 17, 2013, the Commissioner of the Massachusetts Department of Revenue (“Commissioner”) issued a notice of assessment to a j2 Global affiliate for sales and use tax for the period of July 1, 2003 through December 31, 2011. On July 22, 2014, the Commissioner denied the j2 Global affiliate’s application for abatement. On September 18, 2014, the j2 Global affiliate petitioned the Massachusetts Appellate Tax Board for abatement of the tax asserted in the notice of assessment (No. C325426). A trial was held on December 16, 2015. On May 18, 2017, the Appellate Board decided in favor of the Commonwealth of Massachusetts and the Company paid and expensed the tax assessment. The j2 Global affiliate has requested the findings of fact and conclusions of law from the Appellate Board. On October 16, 2013, a j2 Global affiliate entered an appearance as a plaintiff in a multi-district litigation pending in the Northern District of Illinois (No. 1:12-cv-06286). In this litigation, Unified Messaging Solutions, LLC (“UMS”), a company with rights to assert certain patents owned by the j2 Global affiliate, has asserted five j2 Global patents against a number of defendants. While claims against some defendants have been settled, other defendants have filed counterclaims for, among other things, non-infringement, unenforceability, and invalidity of the patents-in-suit. On December 20, 2013, the Northern District of Illinois issued a claim construction opinion and, on June 13, 2014, entered a final judgment of non-infringement for the remaining defendants based on that claim construction. UMS and the j2 Global affiliate filed a notice of appeal to the Federal Circuit on June 27, 2014 (No. 14-1611). On December 8, 2017, the Federal Circuit affirmed the decision of the lower court. On January 21, 2016, Davis Neurology, P.A. filed a putative class action against two j2 Global affiliates in the Circuit Court for the County of Pope, State of Arkansas (58-cv-2016-40), alleging violations of the TCPA. The case was ultimately removed to the U.S. District Court for the Eastern District of Arkansas (the “Eastern District of Arkansas”) (No. 4:16-cv-00682). On June 6, 2016, the j2 Global affiliates filed a motion for judgment on the pleadings. On March 20, 2017, the Eastern District of Arkansas dismissed all claims against the j2 Global affiliates. On April 17, 2017, Davis Neurology filed a notice of appeal. On June 20, 2017, Davis Neurology filed its appeal brief. On August 4, 2017 j2 Global affiliates filed a response brief. On August 21, 2017, Davis Neurology filed a reply brief. Oral argument was held January 11, 2018. j2 Global affiliates submitted a supplemental letter brief on January 31, 2018. Davis Neurology submitted a supplemental letter brief on February 15, 2018. The appeal is pending. j2 Global does not believe, based on current knowledge, that the foregoing legal proceedings or claims, after giving effect to existing reserves, are likely to have a material adverse effect on the Company’s consolidated financial position, results of operations, or cash flows. However, depending on the amount and timing, an unfavorable resolution of some or all of these matters could have a material effect on j2 Global’s consolidated financial position, results of operations, or cash flows in a particular period. The Company has not accrued for any material loss contingencies relating to these legal proceedings because materially unfavorable outcomes are not considered probable by management. It is the Company’s policy to expense as incurred legal fees related to various litigations. Credit Agreement On December 5, 2016, j2 Global entered into a Credit Agreement (the Credit Agreement) with MUFG Union Bank, N.A., as administrative agent, and certain other lenders from time to time party thereto (collectively, the Lenders). Pursuant to the Credit Agreement, the Lenders provided j2 Global with a credit facility of $225.0 million (the Credit Facility). On June 27, 2017, the Company paid off the entire line of credit of $225.0 million , in addition to interest and miscellaneous fees of $0.5 million and terminated the Credit Agreement. Operating Leases j2 Global leases certain facilities and equipment under non-cancelable operating leases which expire at various dates through 2025. Office and equipment leases are typically for terms of three to five years and generally provide renewal options for terms up to an additional five years. In most cases, the Company expects leases that expire will be renewed or replaced by other leases with similar terms. Future minimum lease payments at December 31, 2017 under non-cancelable operating leases (with initial or remaining lease terms in excess of one year) are as follows (in thousands): Lease Payments Fiscal Year: 2018 $ 18,589 2019 17,325 2020 13,721 2021 12,049 2022 11,199 Thereafter 13,258 Total minimum lease payments $ 86,141 Rental expense for the years ended December 31, 2017 , 2016 and 2015 was $15.3 million , $10.6 million and $9.0 million , respectively. Sublease Total sublease income for the years ended December 31, 2017 , 2016 and 2015 was $0.7 million and $0.6 million and $0.5 million , respectively. Total estimated aggregate sublease income to be received in the future is $9.0 million . Non-Income Related Taxes As a provider of cloud services for business, the Company does not provide telecommunications services. Thus, it believes that its business and its users (by using our services) are generally not subject to various telecommunication taxes. However, several state taxing authorities have challenged this belief and have and may continue to audit and assess our business and operations with respect to telecommunications and other sales taxes. In addition, the application of other indirect taxes (such as sales and use tax, business tax and gross receipt tax) to e-commerce businesses such as j2 Global and our users is a complex and evolving issue. The application of existing, new or future laws could have adverse effects on our business, prospects and operating results. There have been, and will continue to be, substantial ongoing costs associated with complying with the various indirect tax requirements in the numerous markets in which we conduct or will conduct business. The Company is currently under audit for indirect taxes in several states and municipalities. On March 3, 2017, the New York State Department of Taxation and Finance issued a notice of assessment for sales and use tax for the period of March 1, 2009 through February 28, 2014. We have reached a settlement with the Department which has expanded the period up to November 30, 2017. We have accrued $2.80 million as of December 31, 2017. On February 18, 2018, we paid $2.77 million to New York in settlement. On August 24, 2016, the Office of Finance for the City of Los Angeles notified us that they would commence an audit of business and communications taxes for the period of January 1, 2013 through December 31, 2016, which has concluded with no material impact. For other jurisdictions, we currently have no reserves established for these matters, as we have determined that the liability is not probable and estimable. However, it is reasonably possible that such a liability could be incurred, which would result in additional expense, which could materially impact our financial results.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense amounted to $60.5 million , $59.0 million and $23.3 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. Our effective tax rates for 2017 , 2016 and 2015 were 30.3% , 27.9% and 14.8% , respectively. The Company has not completed its accounting for the income tax effects of the 2017 Tax Act. Where the Company has been able to make reasonable estimates of the effects for which its analysis is not yet complete, the Company has recorded provisional amounts in accordance with SEC Staff Accounting Bulletin No. 118. Where the Company has not yet been able to make reasonable estimates of the impact of certain elements, the Company has not recorded any amounts related to those elements and has continued accounting for them in accordance with ASC 740 on the basis of the tax laws in effect immediately prior to the enactment of the 2017 Tax Act. The Company’s accounting for the following elements of the 2017 Tax Act is incomplete. However, the Company was able to make reasonable estimates of certain effects and, therefore, has recorded provisional amounts as follows: Revaluation of deferred tax assets and liabilities: The 2017 Tax Act reduces the U.S. federal corporate tax rate from 35% to 21% for tax years beginning after December 31, 2017. In addition, the 2017 Tax Act makes certain changes to the depreciation rules and implements new limits on the deductibility of certain executive compensation. The Company has evaluated these changes and has recorded a provisional decrease to net deferred tax liabilities of $33.3 million with a corresponding decrease to deferred tax expense. The Company is still completing its calculation of the impact of these changes on its deferred tax balances. Transition tax on unrepatriated foreign earnings: The transition tax on unrepatriated foreign earnings is a tax on previously untaxed accumulated and current earnings and profits (“E&P”) of the Company’s foreign subsidiaries. To determine the amount of the transition tax, the Company must determine, among other factors, the amount of post-1986 E&P of its foreign subsidiaries, as well as the amount of non-U.S. income taxes paid on such earnings. The Company was able to make a reasonable estimate of the transition tax and has recorded a provisional transition tax expense of $49.2 million . The Company is continuing to gather additional information to more precisely compute the amount of the transition tax to complete its calculation of E&P as well as the final determination of non-U.S. income taxes paid. Valuation allowances: The Company must assess whether its valuation allowance analyses for deferred tax assets are affected by various aspects of the 2017 Tax Act (e.g., deemed repatriation of deferred foreign income, future GILTI inclusions, new categories of foreign tax credits). Since, as discussed herein, the Company has recorded provisional amounts related to certain portions of the 2017 Tax Act, any corresponding determination of the need for or change in a valuation allowance is also provisional. Prior to 2017, the Company had recorded valuation allowances for certain tax attributes that the Company estimated were not more likely than not to be utilized prior to their expiration. Based on a preliminary review of its 2017 and future taxable income, the Company has recorded a provisional release of valuation allowance in the amount of $11.9 million with a corresponding deferred tax benefit. The Company’s accounting for the following elements of the 2017 Tax Act is incomplete, and it has not yet been able to make reasonable estimates of the effects of these items. Therefore, no provisional amounts were recorded. Global intangible low taxed income (“GILTI”): The 2017 Tax Act creates a new requirement that certain income (i.e. GILTI) earned by foreign subsidiaries must be included currently in the gross income of the U.S. shareholder. Due to the complexity of the new GILTI tax rules, the Company is continuing to evaluate this provision of the 2017 Tax Act and the application of ASC 740. Under U.S. GAAP, the Company is permitted to make an accounting policy election to either treat taxes due on future inclusions in U.S. taxable income related to GILTI as a current-period expense when incurred or to factor such amounts into the Company’s measurement of its deferred taxes. The Company has not yet completed its analysis of the GILTI tax rules and is not yet able to reasonably estimate the effect of this provision of the 2017 Tax Act or make an accounting policy election for the ASC 740 treatment of the GILTI tax. Therefore, the Company has not recorded any amounts related to potential GILTI tax in its financial statements and has not yet made a policy decision regarding whether to record deferred taxes on GILTI. Indefinite reinvestment assertion: Beginning in 2018, the 2017 Tax Act provides a 100% deduction for dividends received from 10-percent owned foreign corporations by U.S. corporate shareholders, subject to a one-year holding period. Although dividend income is now exempt from U.S. federal tax in the hands of the U.S. corporate shareholders, companies must still apply the guidance of ASC 740-30-25-18 to account for the tax consequences of outside basis differences and other tax impacts of their investments in non-U.S. subsidiaries. While the Company has accrued the transition tax on the deemed repatriated earnings that were previously indefinitely reinvested, the Company was unable to determine a reasonable estimate of the remaining tax liability, if any, under the 2017 Tax Act for its remaining outside basis differences or evaluate how the 2017 Tax Act will affect the Company’s existing accounting position to indefinitely reinvest unremitted foreign earnings. Therefore, the Company has not included a provisional amount for this item in its financial statements for fiscal 2017. The Company will record amounts as needed for this item beginning in the first reporting period during the measurement period in which the Company obtains necessary information and is able to analyze and prepare a reasonable estimate. The provision for income tax consisted of the following (in thousands): Years Ended December 31, 2017 2016 2015 Current: Federal $ 55,804 $ 46,293 $ 21,745 State 3,265 3,874 1,805 Foreign 22,904 22,612 16,816 Total current 81,973 72,779 40,366 Deferred: Federal (15,682 ) (6,822 ) (8,581 ) State 962 (330 ) (3,462 ) Foreign (6,712 ) (6,627 ) (5,040 ) Total deferred (21,432 ) (13,779 ) (17,083 ) Total provision $ 60,541 $ 59,000 $ 23,283 A reconciliation of the statutory federal income tax rate with j2 Global’s effective income tax rate is as follows: Years Ended December 31, 2017 2016 2015 Statutory tax rate 35 % 35 % 35 % State income taxes, net 0.8 1.1 0.3 Foreign rate differential (16.1 ) (14.6 ) (15.8 ) Foreign income inclusion 7.2 9.4 5.4 Foreign tax credit (6.2 ) (5.5 ) (6.1 ) Reserve for uncertain tax positions 3.9 4.7 (3.3 ) Valuation allowance (0.9 ) (1.0 ) 1.8 IRC Section 199 deductions (1.6 ) (1.1 ) (1.2 ) The 2017 Tax Act - provisional transition tax 24.6 — — The 2017 Tax Act - tax rate impact on deferred taxes (16.1 ) — — Other (0.3 ) (0.1 ) (1.3 ) Effective tax rates 30.3 % 27.9 % 14.8 % The Company’s effective rate for each year is normally lower than the 35% U.S. federal statutory plus applicable state income tax rates primarily due to earnings of j2 Global’s subsidiaries outside of the U.S. in jurisdictions where the effective tax rate is lower than in the U.S. Deferred tax assets and liabilities result from differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities. Temporary differences and carryforwards which give rise to deferred tax assets and liabilities are as follows (in thousands): Years Ended December 31, 2017 2016 Deferred tax assets: Net operating loss carryforwards $ 29,317 $ 59,806 Tax credit carryforwards 2,645 16,281 Accrued expenses 3,165 14,759 Allowance for bad debt 1,570 2,624 Share-based compensation expense 6,476 5,631 Basis difference in fixed assets 1,881 2,195 Impairment of investments 48 74 Deferred revenue 728 2,361 State taxes 1,777 1,758 Other 14,165 9,227 61,772 114,716 Less: valuation allowance (197 ) (12,028 ) Total deferred tax assets $ 61,575 $ 102,688 Deferred tax liabilities: Basis difference in intangible assets $ (70,252 ) $ (98,830 ) Prepaid insurance (616 ) (246 ) Convertible debt (27,504 ) (36,592 ) Other (1,467 ) (2,088 ) Total deferred tax liabilities (99,839 ) (137,756 ) Net deferred tax liabilities $ (38,264 ) $ (35,068 ) The Company had approximately $61.6 million and $102.7 million in deferred tax assets as of December 31, 2017 and 2016 , respectively, related primarily to net operating loss carryforwards, tax credit carryforwards and accrued expenses treated differently between its financial statements and its tax returns. Based on the weight of available evidence, the Company assesses whether it is more likely than not that some portion or all of a deferred tax asset will not be realized. If necessary, j2 Global records a valuation allowance sufficient to reduce the deferred tax asset to the amount that is more likely that not to be realized. The deferred tax assets should be realized through future operating results and the reversal of temporary differences. As of December 31, 2017 , the Company had federal net operating loss carryforwards (“NOLs”) of $102.2 million , after considering substantial restrictions on the utilization of these NOLs due to “ownership changes”, as defined in the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”). j2 Global currently estimates that all of the above-mentioned federal NOLs will be available for use before their expiration. These NOLs expire through the year 2036 . The $102.2 million NOL carryforward amount includes $89.1 million acquired pursuant to the Everyday Health transaction. As of December 31, 2017 and 2016 , the Company has foreign tax credits of zero and $11.9 million , respectively. The Company has provided a valuation allowance on the foreign tax credits of zero and $11.9 million , respectively, as the weight of available evidence does not support full utilization of these credits. The foreign tax credits were fully utilized in 2017 as a result of the transition tax on repatriated foreign earnings. If these tax credits were not fully utilized, the foreign tax credits would have expired in the year 2025. In addition, as of December 31, 2017 and 2016 , the Company had state research and development tax credits of $2.3 million and $3.5 million , respectively, which last indefinitely. Certain tax payments are prepaid during the year and included within prepaid expenses and other current assets on the consolidated balance sheet. The Company’s prepaid tax payments were $6.0 million and zero at December 31, 2017 and 2016 , respectively. Uncertain Income Tax Positions Tax positions are evaluated in a two-step process. The Company first determines whether it is more likely than not that a tax position will be sustained upon examination. If a tax position meets the more-likely-than-not recognition threshold, it is then measured to determine the amount of benefit to recognize in the financial statements. The tax position is measured as the largest amount of benefit that is greater than 50% likely of being realized upon ultimate settlement. The Company classifies gross interest and penalties and unrecognized tax benefits that are not expected to result in payment or receipt of cash within one year as non-current liabilities in the consolidated balance sheets. As of December 31, 2017 , the total amount of unrecognized tax benefits was $45.0 million , of which $39.8 million , if recognized, would affect the Company’s effective tax rate. As of December 31, 2016, the total amount of unrecognized tax benefits was $41.2 million , of which $37.0 million , if recognized, would affect the Company’s effective tax rate. As of December 31, 2015, the total amount of unrecognized tax benefits was $32.5 million , of which $29.8 million , if recognized would affect the Company’s effective tax rate. The aggregate changes in the balance of unrecognized tax benefits, which excludes interest and penalties, for 2017 , 2016 and 2015 , is as follows (in thousands): Years Ended December 31, 2017 2016 2015 Beginning balance $ 41,218 $ 32,536 $ 34,635 Increases related to tax positions during a prior year — 2,082 10,361 Decreases related to tax positions taken during a prior year (401 ) — (17,107 ) Increases related to tax positions taken in the current year 7,223 6,703 8,841 Settlements (2,639 ) — (4,194 ) Decreases related to expiration of statute of limitations (389 ) (103 ) — Ending balance $ 45,012 $ 41,218 $ 32,536 The Company includes interest and penalties related to unrecognized tax benefits within the provision for income taxes. As of December 31, 2017 , 2016 and 2015 , the total amount of interest and penalties accrued was $7.2 million , $5.3 million and $3.4 million , respectively, which is classified as non-current liabilities in the consolidated balance sheets. In connection with tax matters, the Company recognized interest and penalty (benefit) expense in 2017 , 2016 and 2015 of $2.1 million , $1.9 million and $(1.4) million , respectively. Uncertain income tax positions are reasonably possible to significantly change during the next 12 months as a result of completion of income tax audits and expiration of statutes of limitations. At this point it is not possible to provide an estimate of the amount, if any, of significant changes in reserves for uncertain income tax positions as a result of the completion of income tax audits that are reasonably possible to occur in the next 12 months. In addition, the Company cannot currently estimate the amount of, if any, uncertain income tax positions which will be released in the next 12 months as a result of expiration of statutes of limitations due to ongoing audits. As a result of ongoing federal, state and foreign income tax audits (discussed below), it is reasonably possible that our entire reserve for uncertain income tax positions for the periods under audit will be released. It is also reasonably possible that the Company’s reserves will be inadequate to cover the entire amount of any such income tax liability. Income before income taxes included income from domestic operations of $61.9 million , $84.8 million and $61.0 million for the years ended December 31, 2017 , 2016 and 2015 , respectively, and income from foreign operations of $138.1 million , $126.6 million and $95.9 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. Income Tax Audits: In November 2015, the U.S. Internal Revenue Service (“IRS”) began an income tax audit of the Company’s 2012 and 2013 tax years. In March 2016, the IRS expanded its income tax audit to include the Company’s 2014 tax year. Additionally, the Company was notified on March 22, 2017 that the IRS will be auditing Everyday Health’s 2014 tax year. In December 2017, the Company was notified by the IRS that the 2014 audit of Everyday Health will be concluded with no changes. The Company is under audit by the California Franchise Tax Board (“FTB”) for tax years 2012 and 2013. The FTB, however, has agreed to suspend its audit for 2012 and 2013 pending the outcome of the IRS audit for such tax years. The Company is under income tax audit by the New York State Department of Taxation and Finance (“NYS”) for tax years 2011 through 2013. In March 2017, NYS expanded its income tax audit to include the Company’s 2014 tax year. In September 2017, the Massachusetts Department of Revenue notified the Company that it will commence an audit of income tax for tax years 2014 and 2015. In addition, the Georgia Department of Revenue notified the Company that it will commence an audit of income tax for tax years 2014 through 2016. The Company is currently under audit by the French tax authorities for tax years 2011 to 2016. The audit is in the preliminary fact gathering stage. It is reasonably possible that these audits may conclude in the next 12 months and that the uncertain tax positions the Company has recorded in relation to these tax years may change compared to the liabilities recorded for these periods. If the recorded uncertain tax positions are inadequate to cover the associated tax liabilities, the Company would be required to record additional tax expense in the relevant period, which could be material. If the recorded uncertain tax positions are adequate to cover the associated tax liabilities, the Company would be required to record any excess as reduction in tax expense in the relevant period, which could be material. However, it is not currently possible to estimate the amount, if any, of such change.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2017
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Stockholders’ Equity Preferred Stock Exchange In November 2014, the Company provided holders of the Company’s Series A Preferred Stock (“j2 Series A Stock”) and the Company’s Series B Preferred Stock (“j2 Series B Stock”) an exchange right in which shares may be exchanged for j2 common stock. The exchange right associated with the shares of j2 Series A Stock provided that such shares were immediately exercisable at an exchange ratio of 20.4319 shares of j2 common stock per share of j2 Series A Stock (the “Series A Exchange Ratio”). Both holders of the j2 Series A Stock exercised this exchange right which resulted in the issuance of 235,665 shares of j2 common stock. The exchange right associated with the vested shares of the j2 Series B Stock is exercisable during specified exchange periods at an exchange ratio of 31.8094 shares of j2 common stock per share of j2 Series B Stock (the “Series B Exchange Ratio”). Holders of vested j2 Series B Stock exercised this exchange right which resulted in the issuance of 88,623 and 91,737 shares of j2 common stock during fiscal years 2017 and 2016 , respectively. In connection with the exercise of the exchange right and the resulting extinguishment of the j2 Series A Stock, the Company recorded the difference between the carrying value of the Series A and the fair value of the j2 common stock exchanged within retained earnings as a preferred stock dividend. In connection with the exercise of the exchange right associated with j2 Series B Stock, the Company recognized incremental fair value in the amount of $6.3 million and recorded additional share-based compensation in the amount of $1.2 million and $1.3 million for the years ended December 31, 2017 and 2016, respectively. The remaining amount of unrecognized incremental fair value will be recognized over the remaining service period. The Series B Exchange Ratio is adjusted in the event of a subdivision of the outstanding j2 common stock or j2 Series B Stock, a declaration of a dividend payable in shares of j2 common stock or j2 Series B Stock, a declaration of a dividend payable in a form other than shares in an amount that has a material effect on the value of shares of j2 common stock or j2 Series B Stock, a combination or consolidation of the outstanding j2 common stock or j2 Series B Stock into a lesser number of shares of j2 common stock or j2 Series B Stock, respectively, specified changes in control, a recapitalization, a reclassification, or a similar occurrence, the Company shall adjust the Series B Exchange Ratio as it deems appropriate in its sole discretion. Common Stock Repurchase Program In February 2012, the Company’s Board of Directors approved a program authorizing the repurchase of up to five million shares of j2 Global common stock through February 20, 2013 (the “2012 Program”) which was subsequently extended through February 19, 2019 (see Note 20 - Subsequent Events). On February 15, 2012, the Company entered into a Rule 10b5-1 trading plan with a broker to facilitate the repurchase program. No shares were repurchased under the share repurchase program for the years ended December 31, 2017 and 2016. Cumulatively at December 31, 2017 , 2.1 million shares were repurchased at an aggregate cost of $58.6 million (including an immaterial amount of commission fees). In July 2016, the Company acquired and subsequently retired 935,231 shares of j2 Global common stock in connection with the acquisition of Integrated Global Concepts, Inc. (see Note 3 - Business Acquisitions). As a result of the purchase of j2 Global common stock, the Company’s Board of Directors approved a reduction in the number of shares available for purchase under the 2012 Program by the same amount leaving 1,938,689 shares of j2 Global common stock available for purchase under this program. Periodically, participants in j2 Global’s stock plans surrender to the Company shares of j2 Global stock to pay the exercise price or to satisfy tax withholding obligations arising upon the exercise of stock options or the vesting of restricted stock. During the year ended December 31, 2017 , the Company purchased 117,076 shares from plan participants for this purpose. Dividends The following is a summary of each dividend declared during fiscal year 2017 and 2016: Declaration Date Dividend per Common Share Record Date Payment Date February 10, 2016 $ 0.3250 February 23, 2016 March 10, 2016 May 5, 2016 $ 0.3350 May 18, 2016 June 2, 2016 August 2, 2016 $ 0.3450 August 17, 2016 September 1, 2016 November 1, 2016 $ 0.3550 November 18, 2016 December 5, 2016 February 9, 2017 $ 0.3650 February 22, 2017 March 9, 2017 May 4, 2017 $ 0.3750 May 19, 2017 June 2, 2017 August 2, 2017 $ 0.3850 August 14, 2017 September 1, 2017 October 31, 2017 $ 0.3950 November 17, 2017 December 5, 2017 On February 2, 2018 , the Com pany’s Board of Directors declared a quarterly cash dividend of $0.4050 per share of common stock payable on March 9, 2018 to all stockholders of record as of the close of business on February 22, 2018 (see Note 20 - Subsequent Events). Future dividends will be subject to Board approval.

Stock Options And Employee Stoc

Stock Options And Employee Stock Purchase Plan	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Options And Employee Stock Purchase Plan	Stock Options and Employee Stock Purchase Plan j2 Global’s share-based compensation plans include the 2007 Stock Plan, the 2015 Stock Plan and the 2001 Employee Stock Purchase Plan. Each plan is described below. (a) The 2007 Stock Option Plan and the 2015 Stock Option Plan In October 2007, j2 Global’s Board of Directors adopted the j2 Global, Inc. 2007 Stock Option Plan (the “2007 Plan”). The 2007 Plan provides for the granting of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock, restricted stock units and other share-based awards. The number of authorized shares of common stock that may be used for 2007 Plan purposes is 4,500,000 . Options under the 2007 Plan may be granted at exercise prices determined by the Board of Directors, provided that the exercise prices shall not be less than the fair market value of j2 Global’s common stock on the date of grant for incentive stock options and not less than 85% of the fair market value of j2 Global’s common stock on the date of grant for non-statutory stock options. The 2007 Plan terminated on February 14, 2017. In May 2015, j2 Global’s Board of Directors adopted the j2 Global, Inc. 2015 Stock Option Plan (the “2015 Plan”). The 2015 Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock, restricted stock units, performance shares, performance share units and other share-based awards and is intended as a successor plan to the 2007 Stock Plan since no further grants will be made under the 2007 Stock Plan. 4,200,000 shares of common stock are authorized to be used for 2015 Plan purposes. Options under the 2015 Plan may be granted at exercise prices determined by the Board of Directors, provided that the exercise prices shall not be less than the higher of the par value or 100% of the fair market value of j2 Global’s common stock subject to the option on the date the option is granted. At December 31, 2017 , 2016 and 2015 , options to purchase 361,875 , 353,258 and 457,792 shares of common stock were exercisable under and outside of the 2015 Plan and the 2007 Plan combined, at weighted average exercise prices of $29.92 , $26.10 and $24.78 , respectively. Stock options generally expire after 10 years and vest over a 5 -year period. All stock option grants are approved by “outside directors” within the meaning of Internal Revenue Code Section 162(m). Stock Options Stock option activity for the years ended December 31, 2017 , 2016 and 2015 is summarized as follows: Number of Shares Weighted-Average Exercise Price Weighted-Average Remaining Contractual Life (In Years) Aggregate Intrinsic Value Options outstanding at January 1, 2015 725,649 $ 24.29 Granted 62,000 67.35 Exercised (221,221 ) 22.41 Canceled — — Options outstanding at December 31, 2015 566,428 $ 29.74 Granted — — Exercised (142,870 ) 26.04 Canceled (9,700 ) 26.92 Options outstanding at December 31, 2016 413,858 $ 31.09 Granted — — Exercised (38,183 ) 29.03 Canceled — — Options outstanding at December 31, 2017 375,675 $ 31.30 2.5 $16,429,727 Exercisable at December 31, 2017 361,875 $ 29.92 2.3 $16,323,743 Vested and expected to vest at December 31, 2017 373,168 $ 31.05 2.4 $16,410,477 For the years ended December 31, 2017, 2016 and 2015, j2 Global granted zero , zero and 62,000 options, respectively, to purchase shares of common stock pursuant to the 2015 Plan. These stock options vest 20% per year and expire 10 years from the date of grant. The per share weighted-average grant-date fair values of stock options granted during the period ended December 31, 2015 was $15.22 . There were no stock options granted during the years 2017 and 2016. The total intrinsic values of options exercised during the years ended December 31, 2017 , 2016 and 2015 was $2.1 million , $5.6 million and $10.5 million , respectively. The total fair value of options vested during the years ended December 31, 2017 , 2016 and 2015 was $0.6 million , $0.6 million and $0.7 million , respectively. Cash received from options exercised under all share-based payment arrangements for the years ended December 31, 2017 , 2016 and 2015 was $1.1 million , $3.6 million and $5.0 million , respectively. The actual tax benefit realized for the tax deductions from option exercises under the share-based payment arrangements totaled $0.7 million , $1.9 million and $3.7 million , respectively, for the years ended December 31, 2017 , 2016 and 2015 . The following table summarizes information concerning outstanding and exercisable options as of December 31, 2017 : Options Outstanding Exercisable Options Range of Exercise Prices Number Outstanding December 31, 2017 Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number Exercisable December 31, 2017 Weighted Average Exercise Price $17.19 22,000 1.18 years $ 17.19 22,000 $ 17.19 20.91 45,558 0.34 years 20.91 45,558 20.91 21.67 50,040 1.35 years 21.67 50,040 21.67 22.92 84,092 2.35 years 22.92 84,092 22.92 24.61 - 25.93 14,500 4.02 years 25.13 14,500 25.13 27.60 700 3.08 years 27.60 700 27.60 29.34 75,585 3.36 years 29.34 75,585 29.34 29.53 13,700 4.17 years 29.53 13,700 29.53 31.07 7,500 3.82 years 31.07 7,500 31.07 67.35 62,000 3.51 years 67.35 48,200 67.35 $17.19 - $67.35 375,675 2.46 years $ 31.30 361,875 $ 29.92 As discussed in Note 12, “Stockholders’ Equity”, the Company provided holders of j2 Series B Stock an exchange right in which j2 Series B Stock may be exchanged for j2 common stock during specified exchange periods. The Company determined that such exchange right represents a grant under the 2007 Plan for the year ended December 31, 2014, and accordingly, reduced the awards available under the 2007 Plan. At December 31, 2017 , there were 3,450,474 additional shares underlying options, shares of restricted stock and other share-based awards available for grant under the 2015 Plan, and no additional shares are available for grant under or outside of the 2007 Plan. The Company recognized $0.4 million , $0.4 million and $0.7 million of compensation expense related to stock options for the years ended December 31, 2017, 2016 and 2015, respectively. As of December 31, 2017 , there was $0.2 million of total unrecognized compensation expense related to nonvested share-based compensation options granted under the 2015 Plan and the 2007 Plan. That expense is expected to be recognized ratably over a weighted average period of 2.35 years (i.e., the remaining requisite service period). Fair Value Disclosure j2 Global uses the Black-Scholes option pricing model to calculate the fair value of each option grant. The expected volatility is based on historical volatility of the Company’s common stock. The Company estimates the expected term based upon the historical exercise behavior of our employees. The risk-free interest rate is based on U.S. Treasury zero-coupon issues with a term equal to the expected term of the option assumed at the date of grant. The Company uses an annualized dividend yield based upon the per share dividends declared by its Board of Directors. Estimated forfeiture rates were 14.3% , 12.7% and 14.1% as of December 31, 2017 , 2016 and 2015 , respectively. The weighted-average fair values of stock options granted have been estimated utilizing the following assumptions: Years Ended December 31, 2017 2016 2015 Risk-free interest rate —% —% 1.6% Expected term (in years) 0.0 0.0 5.2 Dividend yield —% —% 1.8% Expected volatility —% —% 28.1% Weighted average volatility —% —% 28.1% Restricted Stock and Restricted Stock Units j2 Global has awarded restricted stock and restricted stock units to its Board of Directors and senior staff pursuant to the the 2007 Plan and the 2015 Plan. Compensation expense resulting from restricted stock and restricted unit grants is measured at fair value on the date of grant and is recognized as share-based compensation expense over the applicable vesting period. Beginning in fiscal year 2012 vesting periods are approximately one year for awards to members of the Company’s Board of Directors and five years for senior staff. The Company granted 300,330 , 317,914 and 252,940 shares of restricted stock and restricted units during the years ended December 31, 2017 , 2016 and 2015 , respectively, and recognized $22.2 million , $13.2 million and $11.0 million , respectively of related compensation expense. As of December 31, 2017 , the Company had unrecognized share-based compensation cost of $36.6 million associated with these awards. This cost is expected to be recognized over a weighted-average period of 3.9 years for awards and 3.3 years for units. The total fair value of restricted stock and restricted stock units vested during the years ended December 31, 2017 , 2016 and 2015 was $15.1 million , $8.0 million and $6.4 million , respectively. The actual tax benefit realized for the tax deductions from the vesting of restricted stock awards and units totaled $2.3 million , $3.5 million and $3.8 million , respectively, for the years ended December 31, 2017 , 2016 and 2015 . In accordance with ASC 718, share-based compensation is recognized on dividends paid related to nonvested restricted stock not expected to vest, which amounted to approximately $0.1 million , $0.1 million and $0.1 million for the years ended December 31, 2017 , 2016 and 2015, respectively. During the year, the Company accelerated the vesting of certain shares held by employees which were surrendered to the Company to satisfy tax withholding obligations in connection with such employees’ restricted stock. The Company recognized share-based compensation of $1.4 million during the year due to this vesting acceleration. In connection with Nehemia Zucker’s resignation as Chief Executive Officer effective as of December 31, 2017, all of his outstanding and unvested stock options and time-based restricted shares, along with the tranche of performance-vesting restricted shares that was then next scheduled to vest, vested in full on December 29, 2017. As a result, the Company has accelerated the recognition of share-based compensation expense associated with these awards which impacted the fourth quarter by approximately $5.1 million. Restricted Stock - Awards with Market Conditions j2 Global has awarded certain key employees market-based restricted stock awards pursuant to the 2015 Plan. The market-based awards have vesting conditions that are based on specified stock price targets of the Company’s common stock. Market conditions were factored into the grant date fair value using a Monte Carlo valuation model, which utilized multiple input variables to determine the probability of the Company achieving the specified stock price targets with a 20-day and 30-day lookback (trading days) for 2016 and 2017, respectively. Stock-based compensation expense related to an award with a market condition will be recognized over the requisite service period using the graded-vesting method regardless of whether the market condition is satisfied, provided that the requisite service period has been completed. During the year ended December 31, 2017 and 2016 , the Company awarded 85,825 and 106,780 market-based restricted stock awards, respectively. The per share weighted average grant-date fair values of the market-based restricted stock awards granted during the years ended December 31, 2017 and 2016 were $72.20 and $44.67 , respectively. The weighted-average fair values of market-based restricted stock awards granted have been estimated utilizing the following assumptions: December 31, 2017 December 31, 2016 Underlying stock price at valuation date $ 91.17 $ 63.73 Expected volatility 29.0 % 29.8 % Risk-free interest rate 2.17 % 1.51 % Restricted stock award activity for the years ended December 31, 2017 , 2016 and 2015 is set forth below: Shares Weighted-Average Grant-Date Fair Value Nonvested at January 1, 2015 814,050 $ 26.57 Granted 234,540 68.11 Vested (254,871 ) 25.16 Canceled (88,915 ) 40.97 Nonvested at December 31, 2015 704,804 $ 39.08 Granted 296,414 41.27 Vested (255,503 ) 31.27 Canceled (40,700 ) 63.95 Nonvested at December 31, 2016 705,015 $ 41.40 Granted 289,230 61.34 Vested (381,411 ) 39.71 Canceled (7,268 ) 76.08 Nonvested at December 31, 2017 605,566 $ 51.57 Restricted stock unit activity for the years ended December 31, 2017 , 2016 and 2015 is set forth below: Number of Weighted-Average Aggregate Outstanding at January 1, 2015 102,924 Granted 18,400 Vested (23,221 ) Canceled (41,858 ) Outstanding at December 31, 2015 56,245 Granted 21,500 Vested (14,595 ) Canceled (11,200 ) Outstanding at December 31, 2016 51,950 Granted 11,100 Vested (16,370 ) Canceled (8,280 ) Outstanding at December 31, 2017 38,400 1.8 $ 2,881,152 Vested and expected to vest at December 31, 2017 29,397 1.6 $ 2,205,686 Employee Stock Purchase Plan In May of 2001, j2 Global established the j2 Global, Inc. 2001 Employee Stock Purchase Plan, as amended (the “Purchase Plan”), which provides for the issuance of a maximum of 2,000,000 shares of common stock. Under the Purchase Plan, eligible employees can have up to 15% of their earnings withheld, up to certain maximums, to be used to purchase shares of j2 Global’s common stock at certain plan-defined dates. The price of the common stock purchased under the Purchase Plan for the offering periods is equal to 95% of the fair market value of the common stock at the end of the offering period. During 2017 , 2016 and 2015 , 3,283 , 3,918 and 4,020 shares, respectively were purchased under the Purchase Plan at price ranging from $85.73 to $70.43 per share during 2017. As of December 31, 2017 , 1,623,243 shares were available under the Purchase Plan for future issuance. See Note 20 “Subsequent Events” for changes to the Purchase Plan.

Defined Contribution 401(k) Sav

Defined Contribution 401(k) Savings Plan	12 Months Ended
	Dec. 31, 2017
Defined Contribution 401(k) Savings Plan [Abstract]
Defined Contribution 401(k) Savings Plan	Defined Contribution 401(k) Savings Plan j2 Global has several 401(k) Savings Plans that qualify under Section 401(k) of the Internal Revenue Code. Eligible employees may contribute a portion of their salary through payroll deductions, subject to certain limitations. The Company may make annual contributions at its sole discretion to these plans. For the years ended December 31, 2017 , 2016 and 2015, the Company incurred expenses of $3.0 million , $1.8 million and $1.9 million , respectively, for contributions to these 401(k) Savings Plans

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share Reconciliation [Abstract]
Earnings Per Share	Earnings Per Share The components of basic and diluted earnings per share are as follows (in thousands, except share and per share data): Years Ended December 31, 2017 2016 2015 Numerator for basic and diluted net income per common share: Net income attributable to j2 Global, Inc. common shareholders $ 139,425 $ 152,439 $ 133,636 Net income available to participating securities (a) (1,792 ) (2,242 ) (2,159 ) Net income available to j2 Global, Inc. common shareholders 137,633 150,197 131,477 Denominator: Weighted-average outstanding shares of common stock 47,586,242 47,668,357 47,627,853 Dilutive effect of: Equity incentive plans 228,166 201,660 293,911 Convertible debt (b) 854,619 93,209 165,996 Common stock and common stock equivalents 48,669,027 47,963,226 48,087,760 Net income per share: Basic $ 2.89 $ 3.15 $ 2.76 Diluted $ 2.83 $ 3.13 $ 2.73 (a) Represents unvested share-based payment awards that contain certain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). (b) Represents the incremental shares issuable upon conversion of the Convertible Notes due June 15, 2029 by applying the treasury stock method when the average stock price exceeds the conversion price of the Convertible Notes (see Note 9 - Long Term Debt) For the years ended December 31, 2017 , 2016 and 2015 , there were zero options outstanding, respectively, which were excluded from the computation of diluted earnings per share because the exercise prices were greater than the average market price of the common shares.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2017
Segments, Geographical Areas [Abstract]
Segment Information	Segment Information The Company’s business segments are based on the organization structure used by management for making operating and investment decisions and for assessing performance. j2 Global’s reportable business segments are: (i) Cloud Services; and (ii) Digital Media. The Company’s Cloud Services segment is driven primarily by subscription revenues that are relatively higher margin, stable and predictable from quarter to quarter with some seasonal weakness in the fourth quarter. The Cloud Services segment also includes the results of our IP licensing business, which can vary dramatically in both revenues and profitability from period to period. The Company’s Digital Media segment is driven primarily by advertising revenues, has relatively higher sales and marketing expense and has seasonal strength in the fourth quarter. Information on reportable segments and reconciliation to consolidated income from operations is as follows (in thousands): Years Ended December 31, 2017 2016 2015 Revenue by segment: Cloud Services $ 578,956 $ 566,938 $ 504,638 Digital Media 538,939 307,463 216,374 Elimination of inter-segment revenues (57 ) (146 ) (197 ) Total revenue 1,117,838 874,255 720,815 Direct costs by segment (1) : Cloud Services 352,912 356,059 294,436 Digital Media 490,871 256,763 185,937 Direct costs by segment (1) : 843,783 612,822 480,373 Cloud Services operating income (2) 226,044 210,879 210,202 Digital Media operating income 48,068 50,700 30,437 Segment operating income 274,112 261,579 240,639 Global operating costs (2)(3) 28,404 19,013 41,257 Income from operations $ 245,708 $ 242,566 $ 199,382 (1) Direct costs for each segment include cost of revenues and other operating expenses that are directly attributable to the segment, such as employee compensation expense, local sales and marketing expenses, engineering and network operations expenses, depreciation and amortization and other administrative expenses. (2) During 2016, the Company determined certain personnel and third-party costs were directly attributable to a particular segment. As a result, these costs were no longer classified as Global operating costs in 2016. If such costs in 2015 were classified consistent with the 2016 presentation, the operating income for Cloud Services segment would have been $189.1 million and Global operating costs would have been $20.2 million, respectively. (3) Global operating costs include general and administrative and other corporate expenses that are managed on a global basis and that are not directly attributable to any particular segment. 2017 2016 Assets: Cloud Services $ 1,078,577 $ 911,327 Digital Media 1,317,113 1,124,535 Total assets from reportable segments 2,395,690 2,035,862 Corporate 57,403 26,466 Total assets $ 2,453,093 $ 2,062,328 2017 2016 2015 Capital expenditures: Cloud Services $ 7,031 $ 6,113 $ 7,546 Digital Media 32,564 18,633 9,389 Total from reportable segments 39,595 24,746 16,935 Corporate — — 362 Total capital expenditures $ 39,595 $ 24,746 $ 17,297 Depreciation and amortization: Cloud Services $ 68,436 $ 79,533 $ 62,385 Digital Media 93,605 42,558 30,008 Total from reportable segments 162,041 122,091 92,393 Corporate — — 820 Total depreciation and amortization $ 162,041 $ 122,091 $ 93,213 j2 Global maintains operations in the U.S., Canada, Ireland, Japan and other countries. Geographic information about the U.S. and all other countries for the reporting periods is presented below. Such information attributes revenues based on jurisdictions where revenues are reported (in thousands). Years Ended December 31, 2017 2016 2015 Revenues: United States $ 830,800 $ 607,285 $ 492,682 Canada 78,099 76,775 74,864 Ireland 74,430 71,340 43,717 All other countries 134,509 118,855 109,552 Total $ 1,117,838 $ 874,255 $ 720,815 December 31, December 31, Long-lived assets: United States $ 452,143 $ 453,053 All other countries 80,571 93,430 Total $ 532,714 $ 546,483

Supplemental Cash Flows Informa

Supplemental Cash Flows Information	12 Months Ended
	Dec. 31, 2017
Supplemental Cash Flows Information [Abstract]
Supplemental Cash Flows Information	Supplemental Cash Flows Information Cash paid for interest during the years ended December 31, 2017 , 2016 and 2015 was $35.8 million , $33.1 million and $33.1 million , respectively, substantially all of which related to interest on outstanding debt and foreign taxes. Cash paid for income taxes net of refunds received was $51.1 million , $37.4 million and $42.0 million during the years ended December 31, 2017 , 2016 and 2015 , respectively. The Company acquired property and equipment for $0.3 million , $0.4 million and $0.6 million during the years ended December 31, 2017 , 2016 and 2015 , respectively, which had not been yet paid at the end of each such year. During the years ended December 31, 2017 , 2016 and 2015 , j2 Global recorded the tax benefit from the exercise of stock options and restricted stock as a reduction of its income tax liability of $2.9 million , $5.4 million and $7.5 million , respectively. In connection with the sale of Tea Leaves during the fourth quarter 2017, the Company received certain equity securities as non cash consideration initially valued in the amount of $57.7 million .

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	12 Months Ended
	Dec. 31, 2017
Accumulated Other Comprehensive Income [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income The following table summarizes the changes in accumulated balances of other comprehensive income, net of tax, for the years ended December 31, 2017 and 2016 (in thousands): Unrealized Gains (Losses) on Investments Foreign Currency Translation Total Balance as of January 1, 2016 $ 2,449 $ (31,573 ) $ (29,124 ) Other comprehensive income (loss) before reclassifications 744 (23,076 ) (22,332 ) Amounts reclassified from accumulated other comprehensive income (3,193 ) — (3,193 ) Net current period other comprehensive loss (2,449 ) (23,076 ) (25,525 ) Balance as of December 31, 2016 $ — $ (54,649 ) $ (54,649 ) Other comprehensive income before reclassifications — 25,559 25,559 Net current period other comprehensive income — 25,559 25,559 Balance as of December 31, 2017 $ — $ (29,090 ) $ (29,090 ) The following table provides details about reclassifications out of accumulated other comprehensive income for the years ended December 31, 2017 and 2016 (in thousands): Details about Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income Year Ended December 31, 2017 Year Ended December 31, 2016 Unrealized gain on available-for-sale investments $ — $ (5,149 ) Other (income) expense, net — (5,149 ) Income before income taxes — 1,956 Income tax expense — (3,193 ) Net income Total reclassifications for the period $ — $ (3,193 ) Net income

Quarterly Results

Quarterly Results	12 Months Ended
	Dec. 31, 2017
Quarterly Results [Abstract]
Quarterly Results	Quarterly Results (unaudited) The following tables contain selected unaudited statement of income information for each quarter of 2017 and 2016 (in thousands, except share and per share data). j2 Global believes that the following information reflects all normal recurring adjustments necessary for a fair presentation of the information for the periods presented. The operating results for any quarter are not necessarily indicative of results for any future period. Year Ended December 31, 2017 Fourth Quarter Third Quarter Second Quarter First Quarter Revenues $ 316,380 $ 273,616 $ 273,174 $ 254,669 Gross profit 270,406 231,245 230,015 213,859 Net income 49,871 32,358 31,376 25,820 Net income per common share: Basic $ 1.03 $ 0.67 $ 0.65 $ 0.54 Diluted $ 1.02 $ 0.66 $ 0.63 $ 0.52 Weighted average shares outstanding Basic 47,721,700 47,609,819 47,547,118 47,463,231 Diluted 48,437,580 48,521,082 48,948,315 48,766,031 Year Ended December 31, 2016 Fourth Third Second First Revenues $ 251,837 $ 210,116 $ 211,800 $ 200,502 Gross profit 211,608 173,124 176,209 166,214 Net income 43,158 45,569 33,770 29,943 Net income per common share: Basic $ 0.90 $ 0.95 $ 0.69 $ 0.62 Diluted $ 0.89 $ 0.94 $ 0.69 $ 0.61 Weighted average shares outstanding Basic 47,348,372 47,310,011 48,055,783 47,966,718 Diluted 47,862,218 47,494,744 48,265,298 48,238,098

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On January 4, 2018, in a cash transaction, the Company acquired certain assets of Lifescript, a California based provider of digital health and wellness solutions. On January 26, 2018, in a cash transaction, the Company acquired all the issued capital of ThreatTrack Security Holdings, Inc., a Florida based provider of cybersecurity solutions. On February 2, 2018 , the Company’s Board of Directors approved a quarterly cash dividend of $0.4050 per share of common stock payable on March 9, 2018 to all stockholders of record as of the close of business on February 22, 2018 . The Company also announced that it extended the Company’s share repurchase program set to expire February 19, 2018 by an additional year. On February 2, 2018, the Company approved an amendment (the “Amendment”) to the Company’s Amended and Restated 2001 Employee Stock Purchase Plan, to be effective May 1, 2018, such that (i) the purchase price for each offering period shall be 85% of the lesser of the fair market value of a share of common stock of the Company (a “Share”) on the beginning or the end of the offering period, rather than 95% of the fair market value of a Share at the end of the offering period, and (ii) each offering period will be six months, rather than three months. On February 2, 2018, the Board appointed Sarah Fay as a director, effective immediately. In February 2018, the Company received a capital call notice from the management of OCV Management, LLC. for approximately $12.2 million, inclusive of certain management fees.

Basis Of Presentation (Policy)

Basis Of Presentation (Policy)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Consolidation, Policy [Policy Text Block]	(a) Principles of Consolidation The accompanying consolidated financial statements include the accounts of j2 Global and its direct and indirect wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. On August 10, 2016, j2 Cloud Services, Inc., a Delaware corporation and subsidiary of the Company, converted into a Delaware limited liability company which continues as j2 Cloud Services, LLC. On August 12, 2016, all of the equity interests in Ziff Davis, LLC, a Delaware limited liability company, and all of the equity interests in Advanced Messaging Technologies, Inc., a Delaware corporation, held by j2 Cloud Services, LLC, a Delaware limited liability company, were distributed to j2 Global, the parent company of j2 Cloud Services, LLC.
Use Of Estimates	(b) Use of Estimates The preparation of consolidated financial statements in accordance with generally accepted accounting principles in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements, including judgments about investment classifications, and the reported amounts of net revenue and expenses during the reporting period. We believe that our most significant estimates are those related to valuation and impairment of marketable securities, valuation of assets acquired and liabilities assumed in connection with business combinations, long-lived and intangible asset impairment, contingent consideration, income taxes and contingencies and allowance for doubtful accounts. On an ongoing basis, management evaluates its estimates based on historical experience and on various other factors that the Company believes to be reasonable under the circumstances. Actual results could materially differ from those estimates.
Allowances For Doubtful Accounts	(c) Allowances for Doubtful Accounts j2 Global reserves for receivables it may not be able to collect. These reserves for the Company’s Cloud Services segment are typically driven by the volume of credit card declines and past due invoices and are based on historical experience as well as an evaluation of current market conditions. These reserves for the Company’s Digital Media segment are typically driven by past due invoices based on historical experience. On an ongoing basis, management evaluates the adequacy of these reserves.
Revenue Recognition	(d) Revenue Recognition Cloud Services The Company’s Cloud Services revenues substantially consist of monthly recurring subscription and usage-based fees, which are primarily paid in advance by credit card. In accordance with GAAP, the Company recognizes revenue when persuasive evidence of an arrangement exists, services have been provided, the sales price is fixed and determinable and collection is probable. The Company defers the portions of monthly, quarterly, semi-annually and annually recurring subscription and usage-based fees collected in advance and recognizes them in the period earned. Additionally, the Company defers and recognizes subscriber activation fees and related direct incremental costs over a subscriber’s estimated useful life. Along with our numerous proprietary Cloud Services solutions, the Company also generates revenues by reselling various third party solutions, primarily through our email security and online backup lines of business. These third party solutions, along with our proprietary products, allow the Company to offer customers a variety of solutions to better meet their needs. The Company determines whether reseller revenue should be reported on a gross or net basis by assessing whether the Company is acting as the principal or an agent in the transaction. If the Company is acting as the principal in a transaction, the Company reports revenue on a gross basis. If the Company is acting as an agent in a transaction, the Company reports revenue on a net basis. In determining whether the Company acts as the principal or an agent, the Company follows the accounting guidance for principal-agent considerations and the Company places the most weight on three factors: whether or not the Company (i) is the primary obligor in the arrangement, (ii) has latitude in determining pricing and (iii) bears credit risk. The Company records revenue on a gross basis with respect to reseller revenue as the Company is the primary obligator in the arrangement, has latitude in determining pricing and bears all credit risk associated with our reseller program partners. j2 Global’s Cloud Services also include patent license revenues generated under license agreements that provide for the payment of contractually determined fully paid-up or royalty-bearing license fees to j2 Global in exchange for the grant of non-exclusive, retroactive and future licenses to our intellectual property, including patented technology. Patent revenues may also consist of revenues generated from the sale of patents. Patent license revenues are recognized when earned over the term of the license agreements. With regard to fully paid-up license arrangements, the Company recognizes as revenue in the period the license agreement is executed the portion of the payment attributable to past use of the intellectual property and amortizes the remaining portion of such payments on a straight-line basis, or pro-rata revenue basis, as appropriate over the life of the licensed patent(s). With regard to royalty-bearing license arrangements, the Company recognizes revenues of license fees earned during the applicable period. With regard to patent sales, the Company recognizes as revenue in the period of the sale the amount of the purchase price over the carrying value of the patent(s) sold. The Cloud Services business also generates revenues by licensing certain technology to third parties. These licensing revenues are recognized when earned in accordance with the terms of the underlying agreement. Generally, revenue is recognized as the third party uses the licensed technology over the period. Digital Media The Company’s Digital Media revenues primarily consist of revenues generated from the sale of advertising campaigns that are targeted to the Company’s proprietary websites and to those websites operated by third parties that are part of the Digital Media business’s advertising network. Revenues for these advertising campaigns are recognized as earned, either when an ad is placed for viewing by a visitor to the appropriate web page or when the visitor “clicks through” on the ad, depending upon the terms with the individual advertiser. Revenues for Digital Media business-to-business operations consist of lead-generation campaigns for IT vendors and are recognized as earned when the Company delivers the qualified leads to the customer. j2 Global also generates Digital Media revenues through the license of certain assets to clients, for the clients’ use in their own promotional materials or otherwise. Such assets may include logos, editorial reviews, or other copyrighted material. Revenues under such license agreements are recognized when the assets are delivered to the client. Also, Digital Media revenues are generated through the license of certain speed testing technology which is recognized when delivered to the client through providing data services primarily to Internet Service Providers (“ISPs”) and wireless carriers which is recognized as earned over the term of the access period. The Digital Media business also generates other types of revenues, including business listing fees, subscriptions to online publications, and from other sources. Such other revenues are recognized as earned. The Company determines whether Digital Media revenue should be reported on a gross or net basis by assessing whether the Company is acting as the principal or an agent in the transaction. If the Company is acting as the principal in a transaction, the Company reports revenue on a gross basis. If the Company is acting as an agent in a transaction, the Company reports revenue on a net basis. In determining whether the Company acts as the principal or an agent, the Company follows the accounting guidance for principal-agent considerations and the Company places the most weight on three factors: whether or not the Company (i) is the primary obligor in the arrangement, (ii) has latitude in determining pricing and (iii) bears credit risk. The Company records revenue on a gross basis with respect to revenue generated (i) by the Company serving online display and video advertising across its owned-and-operated web properties, on third party sites or on unaffiliated advertising networks, (ii) through the Company’s lead-generation business and (iii) through the Company’s Digital Media licensing program. The Company records revenue on a net basis with respect to revenue paid to the Company by certain third-party advertising networks who serve online display and video advertising across the Company’s owned-and-operated web properties and certain third party sites.
Fair Value Measurements	(e) Fair Value Measurements j2 Global complies with the provisions of Financial Accounting Standards Board (“FASB”) Accounting Standard Codification (“ASC”) Topic No. 820, Fair Value Measurements and Disclosures (“ASC 820”), in measuring fair value and in disclosing fair value measurements. ASC 820 provides a framework for measuring fair value and expands the disclosures required for fair value measurements of financial and non-financial assets and liabilities. As of December 31, 2017 , the carrying value of cash and cash equivalents, long-term investments, accounts receivable, interest receivable, accounts payable, accrued expenses, interest payable, customer deposits and long-term debt are reflected in the financial statements at cost. With the exception of long-term investments and long-term debt, cost approximates fair value due to the short-term nature of such instruments. The fair value of the Company’s outstanding debt was determined using the quoted market prices of debt instruments with similar terms and maturities, if available. As of the same dates, the carrying value of other long-term liabilities approximated fair value as the related interest rates approximate rates currently available to j2 Global.
Cash and Cash Equivalents, Policy [Policy Text Block]	(f) Cash and Cash Equivalents j2 Global considers cash equivalents to be only those investments that are highly liquid, readily convertible to cash and with maturities of three months or less at the purchase date.
Investment, Policy [Policy Text Block]	(g) Investments j2 Global accounts for its investments in debt and equity securities in accordance with FASB ASC Topic No. 320, Investments - Debt and Equity Securities (“ASC 320”). Debt investments are typically comprised of corporate and governmental debt securities. Equity securities recorded as available-for-sale represent strategic equity investments. j2 Global determines the appropriate classification of its investments at the time of acquisition and evaluates such determination at each balance sheet date. Held-to-maturity securities are those investments which the Company has the ability and intent to hold until maturity and are recorded at amortized cost. Available-for-sale securities are those investments j2 Global does not intend to hold to maturity and can be sold. Available-for-sale securities are carried at fair value with unrealized gains and losses included in other comprehensive income. Trading securities are carried at fair value, with unrealized gains and losses included in investment income. Securities are accounted for on a specific identification basis, average cost method or other method, as appropriate.
Debt, Policy [Policy Text Block]	(h) Debt Issuance Costs and Debt Discount j2 Global capitalizes costs incurred with borrowing and issuance of debt securities and records debt issuance costs and discounts as a reduction to the debt amount. These costs and discounts are amortized and included in interest expense over the life of the borrowing or term of the credit facility using the effective interest method.
Derivatives, Policy [Policy Text Block]	(i) Derivative Instruments j2 Global currently holds an embedded derivative instrument related to contingent interest in connection with its 3.25% Convertible Notes issued on June 10, 2014. This embedded derivative instrument is carried at fair value with changes recorded to interest expense (see Note 6 - Fair Value Measurements).
Concentration Of Credit Risk	(j) Concentration of Credit Risk All of the Company’s cash, cash equivalents and marketable securities are invested at major financial institutions primarily within the United States, United Kingdom and Ireland. These institutions are required to invest the Company’s cash in accordance with the Company’s investment policy with the principal objectives being preservation of capital, fulfillment of liquidity needs and above market returns commensurate with preservation of capital. The Company’s investment policy also requires that investments in marketable securities be in only highly rated instruments, with limitations on investing in securities of any single issuer. However, these investments are not insured against the possibility of a total or near complete loss of earnings or principal and are inherently subject to the credit risk related to the continued credit worthiness of the underlying issuer and general credit market risks. At December 31, 2017 , the Company’s cash and cash equivalents were maintained in accounts that are insured up to the limit determined by the applicable governmental agency. The Company’s deposits held in qualifying financial institutions in Ireland are fully insured through March 28, 2018 to the extent on deposit prior to March 28, 2013. With respect to the Company’s deposits with financial institutions in other jurisdictions, the insured amount held in other institutions is immaterial in comparison to the total amount of the Company’s cash and cash equivalents held by these institutions which is not insured. These institutions are primarily in the United States and United Kingdom, however, the Company has accounts within several other countries including Australia, Austria, China, France, Germany, Italy, Japan, New Zealand and the Netherlands.
Foreign Currency Transactions and Translations Policy [Policy Text Block]	(k) Foreign Currency Some of j2 Global’s foreign subsidiaries use the local currency of their respective countries as their functional currency. Assets and liabilities are translated at exchange rates prevailing at the balance sheet dates. Revenues, costs and expenses are translated into U.S. Dollars at average exchange rates for the period. Gains and losses resulting from translation are recorded as a component of accumulated other comprehensive income (loss). Net translation gain/(loss) was $25.6 million , $(23.1) million and $(15.1) million for the years ended December 31, 2017 , 2016 and 2015 , respectively. Realized gains and losses from foreign currency transactions are recognized within other (income) expense, net. Foreign exchange losses amounted to $5.8 million , $0.7 million and $0.1 million for the years ended December 31, 2017, 2016 and 2015, respectively.
Property, Plant and Equipment, Policy [Policy Text Block]	(l) Property and Equipment Property and equipment are stated at cost. Equipment under capital leases is stated at the present value of the minimum lease payments. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets. The estimated useful lives of property and equipment range from 1 to 10 years. Fixtures, which are comprised primarily of leasehold improvements and equipment under capital leases, are amortized on a straight-line basis over their estimated useful lives or for leasehold improvements, the related lease term, if less. The Company has capitalized certain internal use software and website development costs which are included in property and equipment. The estimated useful life of costs capitalized is evaluated for each specific project and ranges from 1 to 5 years.
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]	(m) Impairment or Disposal of Long-Lived Assets j2 Global accounts for long-lived assets, which include property and equipment and identifiable intangible assets with finite useful lives (subject to amortization), in accordance with the provisions of FASB ASC Topic No. 360, Property, Plant, and Equipment (“ASC 360”), which requires that long-lived assets be reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability is measured by comparing the carrying amount of an asset to the expected undiscounted future net cash flows generated by the asset. If it is determined that the asset may not be recoverable, and if the carrying amount of an asset exceeds its estimated fair value, an impairment charge is recognized to the extent of the difference. j2 Global assessed whether events or changes in circumstances have occurred that potentially indicate the carrying amount of long-lived assets may not be recoverable. No impairment was recorded in fiscal year 2017, 2016 or 2015. The Company classifies its long-lived assets to be sold as held for sale in the period (i) it has approved and committed to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and other actions required to sell the asset have been initiated, (iv) the sale of the asset is probable, (v) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value, and (vi) it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The Company initially measures a long-lived asset that is classified as held for sale at the lower of its carrying value or fair value less any costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized on the sale of a long-lived asset until the date of sale. Upon designation as an asset held for sale, the Company stops recording depreciation expense on the asset. The Company assesses the fair value of a long-lived asset less any costs to sell at each reporting period and until the asset is no longer is classified as held for sale.
Goodwill and Intangible Assets, Policy [Policy Text Block]	(n) Goodwill and Intangible Assets Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in a business combination. Intangible assets resulting from the acquisitions of entities accounted for using the purchase method of accounting are recorded at the estimated fair value of the assets acquired. Identifiable intangible assets are comprised of purchased customer relationships, trademarks and trade names, developed technologies and other intangible assets. Intangible assets subject to amortization are amortized over the period of estimated economic benefit ranging from 1 to 20 years. In accordance with FASB ASC Topic No. 350, Intangibles - Goodwill and Other (“ASC 350”), goodwill and other intangible assets with indefinite lives are not amortized but tested annually for impairment or more frequently if j2 Global believes indicators of impairment exist. In connection with the annual impairment test for goodwill, the Company has the option to perform a qualitative assessment in determining whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If the Company determines that it was more likely than not that the fair value of the reporting unit is less than its carrying amount, then it performs the impairment test upon goodwill. The impairment test involves a two-step process. The first step involves comparing the fair values of the applicable reporting units with their aggregate carrying values, including goodwill. The Company generally determines the fair value of its reporting units using the income approach methodology of valuation. If the carrying value of a reporting unit exceeds the reporting unit’s fair value, j2 Global performs the second step of the test to determine the amount of impairment loss. The second step involves measuring the impairment by comparing the implied fair values of the affected reporting unit’s goodwill and intangible assets with the respective carrying values. In accordance with ASC 350, the Company performed the annual impairment test for goodwill for fiscal year 2017 using a qualitative assessment primarily taking into consideration macroeconomic, industry and market conditions, overall financial performance and any other relevant company-specific events. The Company performed the annual impairment test for intangible assets with indefinite lives for fiscal 2017 using a qualitative assessment primarily taking into consideration macroeconomic, industry and market conditions, overall financial performance and any other relevant company-specific events. j2 Global concluded that there were no impairments in 2017, 2016 and 2015.
Business Combinations Policy [Policy Text Block]	(o) Contingent Consideration j2 Global measures the contingent earn-out liabilities in connection with acquisitions at fair value on a recurring basis using significant unobservable inputs classified within Level 3 of the fair value hierarchy (see Note 6 - Fair Value Measurements). The Company may use various valuation techniques depending on the terms and conditions of the contingent consideration including a Monte-Carlo simulation. This simulation uses a probability distribution for each significant input to produce hundreds or thousands of possible outcomes and the results are analyzed to determine probabilities of different outcomes occurring. Significant increases or decreases to these inputs in isolation would result in a significantly higher or lower liability with a higher liability capped by the contractual maximum of the contingent earn-out obligation. Ultimately, the liability will be equivalent to the amount paid, and the difference between the fair value estimate and amount paid will be recorded in earnings. The amount paid that is less than or equal to the liability on the acquisition date is reflected as cash used in financing activities in our consolidated statements of cash flows. Any amount paid in excess of the liability on the acquisition date is reflected as cash used in operating activities. j2 Global reviews and re-assess the estimated fair value of contingent consideration on a quarterly basis, and the updated fair value could differ materially from the initial estimates. Changes in the estimated fair value of our contingent earn-out liabilities related to the time component of the present value calculation are reported in interest expense. Adjustments to the estimated fair value related to changes in all other unobservable inputs are reported in operating income.
Income Taxes	(p) Income Taxes j2 Global’s income is subject to taxation in both the U.S. and numerous foreign jurisdictions. Significant judgment is required in evaluating the Company’s tax positions and determining its provision for income taxes. During the ordinary course of business, there are many transactions and calculations for which the ultimate tax determination is uncertain. j2 Global establishes reserves for tax-related uncertainties based on estimates of whether, and the extent to which, additional taxes will be due. These reserves for tax contingencies are established when the Company believes that certain positions might be challenged despite the Company’s belief that its tax return positions are fully supportable. j2 Global adjusts these reserves in light of changing facts and circumstances, such as the outcome of a tax audit or lapse of a statute of limitations. The provision for income taxes includes the impact of reserve provisions and changes to reserves that are considered appropriate. j2 Global accounts for income taxes in accordance with FASB ASC Topic No. 740, Income Taxes (“ASC 740”), which requires that deferred tax assets and liabilities be recognized using enacted tax rates for the effect of temporary differences between the book and tax basis of recorded assets and liabilities. ASC 740 also requires that deferred tax assets be reduced by a valuation allowance if it is more likely than not that some or all of the net deferred tax assets will not be realized. The valuation allowance is reviewed quarterly based upon the facts and circumstances known at the time. In assessing this valuation allowance, j2 Global reviews historical and future expected operating results and other factors, including its recent cumulative earnings experience, expectations of future taxable income by taxing jurisdiction and the carryforward periods available for tax reporting purposes, to determine whether it is more likely than not that deferred tax assets are realizable. ASC 740 provides guidance on the minimum threshold that an uncertain income tax benefit is required to meet before it can be recognized in the financial statements and applies to all income tax positions taken by a company. ASC 740 contains a two-step approach to recognizing and measuring uncertain income tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon settlement. If it is not more likely than not that the benefit will be sustained on its technical merits, no benefit will be recorded. Uncertain income tax positions that relate only to timing of when an item is included on a tax return are considered to have met the recognition threshold. j2 Global recognized accrued interest and penalties related to uncertain income tax positions in income tax expense on its consolidated statements of income.
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	(q) Share-Based Compensation j2 Global accounts for share-based awards in accordance with the provisions of FASB ASC Topic No. 718, Compensation - Stock Compensation (“ASC 718”). Accordingly, j2 Global measures share-based compensation expense at the grant date, based on the fair value of the award, and recognizes the expense over the employee’s requisite service period using the straight-line method. The measurement of share-based compensation expense is based on several criteria, including but not limited to the valuation model used and associated input factors, such as expected term of the award, stock price volatility, risk free interest rate, dividend rate and award cancellation rate. These inputs are subjective and are determined using management’s judgment. If differences arise between the assumptions used in determining share-based compensation expense and the actual factors, which become known over time, j2 Global may change the input factors used in determining future share-based compensation expense. Any such changes could materially impact the Company’s results of operations in the period in which the changes are made and in periods thereafter. The Company estimates the expected term based upon the historical exercise behavior of our employees. j2 Global accounts for option grants to non-employees in accordance with FASB ASC Topic No. 505, Equity, whereby the fair value of such options is determined using the Black-Scholes option pricing model at the earlier of the date at which the non-employee’s performance is complete or a performance commitment is reached.
Earnings Per Share, Policy [Policy Text Block]	(r) Earnings Per Common Share (“EPS”) EPS is calculated pursuant to the two-class method as defined in ASC Topic No. 260, Earnings per Share (“ASC 260”), which specifies that all outstanding unvested share-based payment awards that contain rights to nonforfeitable dividends or dividend equivalents are considered participating securities and should be included in the computation of EPS pursuant to the two-class method. Basic EPS is calculated by dividing net distributed and undistributed earnings allocated to common shareholders, excluding participating securities, by the weighted-average number of common shares outstanding. The Company’s participating securities consist of its unvested share-based payment awards that contain rights to nonforfeitable dividends or dividend equivalents. Diluted EPS includes the determinants of basic EPS and, in addition, reflects the impact of other potentially dilutive shares outstanding during the period. The dilutive effect of participating securities is calculated under the more dilutive of either the treasury method or the two-class method.
Research and Development Expense, Policy [Policy Text Block]	(s) Research, Development and Engineering Research, development and engineering costs are expensed as incurred. Costs for software development incurred subsequent to establishing technological feasibility, in the form of a working model, are capitalized and amortized over their estimated useful lives.
Segment Reporting, Policy [Policy Text Block]	(t) Segment Reporting FASB ASC Topic No. 280, Segment Reporting (“ASC 280”), establishes standards for the way that public business enterprises report information about operating segments in their annual consolidated financial statements and requires that those enterprises report selected information about operating segments in interim financial reports. ASC 280 also establishes standards for related disclosures about products and services, geographic areas and major customers. The Company operates as two segments: (1) Cloud Services and (2) Digital Media.
Advertising Costs, Policy [Policy Text Block]	(u) Advertising Costs Advertising costs are expensed as incurred. Advertising costs for the years ended December 31, 2017, 2016 and 2015 was $143.3 million , $96.8 million and $63.5 million , respectively.
Revenue Recognition, Excise and Sales Taxes	(v) Sales Taxes The Company may collect sales taxes from certain customers which are remitted to governmental authorities as required and are excluded from revenues.
New Accounting Pronouncements, Policy [Policy Text Block]	(w) Recent Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers, as a new Topic, Accounting Standards Codification (“ASC”) Topic 606. The new revenue recognition standard provides a five-step analysis of transactions to determine when and how revenue is recognized. The core principle is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers: Deferral of the Effective Date, which deferred the effective date of the new revenue standard for periods beginning after December 15, 2016 to December 15, 2017, with early adoption permitted but not earlier than the original effective date. In March 2016, the FASB issued ASU 2016-08, Revenue from Contracts with Customers (Topic 606). This ASU is related to reporting revenue gross versus net, or principal versus agent considerations. This ASU is meant to clarify the guidance in ASU 2014-09, Revenue from Contracts with Customers, as it pertains to principal versus agent considerations. Specifically, the guidance addresses how entities should identify goods and services being provided to a customer, the unit of account for a principal versus agent assessment, how to evaluate whether a good or service is controlled before being transferred to a customer, and how to assess whether an entity controls services performed by another party. In April 2016, the FASB issued ASU 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing. This ASU is meant to clarify the guidance in FASB ASU 2014-09, Revenue from Contracts with Customers. Specifically, the guidance addresses an entity’s identification of its performance obligations in a contract, as well as an entity’s evaluation of the nature of its promise to grant a license of intellectual property and whether or not that revenue is recognized over time or at a point in time. In May 2016, the FASB issued ASU 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients. This ASU does not change the core principle of the guidance in Topic 606. Instead, the amendments provide clarifying guidance in a few narrow areas and add some practical expedients. In December 2016, the FASB issued 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers. The amendments in this ASU represent changes to clarify the Codification or to correct unintended application of guidance. This ASU must be applied retrospectively to each period presented or as a cumulative-effect adjustment as of the date of adoption. This ASU is effective January 1, 2018 and the Company is using the modified retrospective method and will present the cumulative effect of applying the standard to all contracts not completed as of the adoption date. The Company has (i) finalized its review of customer contracts for its business segments and assessed the impact of the standard on these contracts; (ii) trained internal stakeholders on the changes to revenue recognition policies; and (iii) assessed the need for appropriate changes to the Company’s business processes and controls to support revenue recognition and disclosures under the new standard. The Company has concluded that the primary change to its revenue recognition for its customer contracts upon adopting ASC 606 is related to the timing of when revenue is recognized. While revenue from certain contracts will continue to be recognized at a point in time, revenue from other contracts is required to be recognized over time. The Company expects changes in the revenue recognition for licensing and patents and has finalized its detailed assessment of customer contracts, including the specific dollar impact of any changes in recognition that will occur on the Company’s consolidated financial statements upon adoption. While the Company will provide expanded disclosures as a result of the adoption of this ASU, the Company does not expect there to be a material impact to the consolidated financial statements as of January 1, 2018. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The amendments in this ASU modify how entities measure equity investments and present changes in the fair value of financial liabilities. Under the new guidance, entities will have to measure equity investments that do not result in consolidation and are not accounted under the equity method at fair value and recognize any changes in fair value in net income unless the investments qualify for the new practicality exception. A practicality exception will apply to those equity investments that do not have a readily determinable fair value and do not qualify for the practical expedient to estimate fair value under ASC 820, Fair Value Measurements, and as such these investments may be measured at cost. This ASU is effective for financial statements issued for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. After adoption, investments within the scope of the standard will be recorded at fair value with changes in fair value recognized in earnings. In February 2016, the FASB issued ASU No. 2016-02, Leases. This ASU establishes a right-of-use (“ROU”) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. This ASU is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. The Company is currently evaluating the impact of this ASU on our financial statements. The Company currently has both capital and operating leases, both domestically and internationally, with varying expiration dates through 2025 in the aggregate amount of $86.1 million for the period ended December 31, 2017. In March 2016, the FASB issued ASU 2016-09, Compensation-Stock Compensation (Topic 718). This ASU is related to simplifications of employee share-based payment accounting. This pronouncement eliminates the APIC pool concept and requires that excess tax benefits and tax deficiencies be recorded in the income statement when awards are settled. The pronouncement also addresses simplifications related to statement of cash flows classification, accounting for forfeitures, and minimum statutory tax withholding requirements. This ASU is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2016. Early adoption is permitted. The new standard requires prospective recognition of excess tax benefits and deficiencies resulting from stock-based compensation awards vesting and exercises be recognized in the income statement. Previously, these amounts were recognized in additional paid-in capital. Net excess tax benefits of $2.3 million for the period ended December 31, 2017, were recognized as a reduction of income tax expense. In addition, ASU 2016-09 requires excess tax benefits and deficiencies to be prospectively excluded from the assumed future proceeds in the calculation of diluted shares, resulting in an insignificant increase in diluted weighted average shares outstanding for the period ended December 31, 2017, which did not have a material impact on earnings per share. The Company has elected to continue to estimate the number of stock-based awards expected to vest, as permitted by ASU 2016-09, rather than electing to account for forfeitures as they occur. $2.3 million for the period ended December 31, 2017. The prior period was not adjusted with the adoption of ASU 2016-09 due to the adoption of this standard on a prospective basis. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The amendments in this ASU replace the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. This ASU is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2019. The adoption of this standard is not expected to have a material impact on our financial statements and related disclosures. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. The new guidance is intended to reduce diversity in practice in how transactions are classified in the statement of cash flows. This ASU is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2017. The Company adopted this guidance on a retrospective basis in 2017 and has determined that there is no material impact on our financial statements. In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other than Inventory. The amendments in this ASU reduce the complexity in the accounting standards by allowing the recognition of current and deferred income taxes for an intra-entity asset transfer, other than inventory, when the transfer occurs. Historically, the income tax consequence was not recognized until the asset was sold to an outside party. This ASU is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. Early adoption is permitted. The Company does not expect the adoption of this ASU to have a material impact on our financial statements and related disclosures. In November 2016, the FASB issued 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash - a consensus of the FASB Emerging Issues Task Force. The amendments in this ASU require restricted cash and restricted cash equivalents to be classified in the statement of cash flows as cash and cash equivalents. The guidance will be applied on a retrospective basis beginning with the earliest period presented. The amendments in this ASU are effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. The Company adopted this guidance on a retrospective basis in 2017 and has determined that there is no material impact on our financial statements. In January 2017, the FASB issued 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business. The amendments in this ASU provide a robust framework to use in determining when a set of assets and activities is a business. This ASU is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. Early adoption is permitted and the standard should be applied prospectively. The Company does not expect the adoption of this ASU to have a material impact on our financial statements and related disclosures. In January 2017, the FASB issued 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. The amendments in this ASU simplify the subsequent measurement of goodwill by eliminating Step 2 from the goodwill impairment test and eliminating the requirement for a reporting unit with a zero or negative carrying amount to perform a qualitative assessment. Instead, under this pronouncement, an entity would perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount and would recognize an impairment change for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized is not to exceed the total amount of goodwill allocated to that reporting unit. In addition, income tax effects will be considered, if applicable. This ASU is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. Early adoption is permitted and should be adopted on a prospective basis. The Company does not expect the adoption of this ASU to have a material impact on our financial statements and related disclosures. In February 2018, the FASB issued 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. The amendments in this ASU allow reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the U.S. federal tax legislation, the Tax Cuts and Jobs Act of 2017 (“2017 Tax Act”). Consequently, the amendments eliminate the stranded tax effects resulting from the 2017 Tax Act and will improve the usefulness of information reported to financial statement users. However, because the amendments only relate to the reclassification of the income tax effects of the 2017 Tax Act, the underlying guidance that requires that the effect of a change in tax laws or rates to be included in income from continuing operations is not affected. This ASU is effective for all entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted and should be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the 2017 Tax Act is recognized. The Company is currently evaluating the effect of this ASU on our financial statements and related disclosures. In February 2018, the FASB issued 2018-03, Technical Corrections and Improvements to Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The amendments in this ASU clarify certain aspects of the guidance issued in ASU 2016-01, Financial Instruments - Overall. As is consistent with other clarifying standards, the amendments are not expected to have a significant effect on the current accounting practice. This ASU is effective for financial statements issued for fiscal years beginning after December 15, 2017, and interim periods beginning after June 15, 2018. Public entities with fiscal years beginning between December 15, 2017 and June 15, 2018 are not required to adopt these amendments until the interim period beginning after June 15, 2018. Early adoption is permitted and should be adopted in conjunction with ASU 2016-01. The Company is currently evaluating the effect of this ASU on our financial statements and related disclosures.
Comparability of Prior Year Financial Data, Policy [Policy Text Block]	Reclassifications Certain prior year reported amounts have been reclassified to conform with the 2017 presentation.

Business Acquisition (Tables)

Business Acquisition (Tables)	12 Months Ended
	Dec. 31, 2017
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The following table summarizes the allocation of the purchase consideration as follows (in thousands): Assets and Liabilities Valuation Accounts receivable $ 14,935 Other assets 1,415 Property and equipment 5,769 Software 18,764 Trade names 22,602 Customer relationships 98,027 Other intangibles 1,873 Goodwill 172,593 Accounts payables and accrued expenses (9,684 ) Deferred revenue (10,764 ) Deferred tax liability (1,316 ) Capital lease (195 ) Total $ 314,019 The following table summarizes the allocation of the purchase consideration for all 2016 acquisitions (in thousands): Assets and Liabilities (1) Valuation Accounts receivable $ 70,922 Other assets 11,730 Property and equipment 11,109 Trade names 5,866 Trademarks 70,300 Customer relationships 85,482 Other intangibles 91,264 Goodwill 333,190 Accounts payables and accrued expenses (62,188 ) Deferred revenue (6,904 ) Deferred tax liability (14,503 ) Capital lease (194 ) Total $ 596,074 The following table summarizes the allocation of the purchase consideration for all 2017 acquisitions (in thousands): Assets and Liabilities Valuation Accounts receivable $ 14,130 Other assets 10,243 Property and equipment 6,411 Deferred tax asset 405 Trade names 20,610 Trademarks 1,373 Customer relationships 61,307 Other intangibles 36,998 Goodwill 121,827 Accounts payables and accrued expenses (27,995 ) Deferred revenue (11,853 ) Deferred tax liability (29,534 ) Total $ 203,922
Business Acquisition, Pro Forma Information [Table Text Block]	The supplemental information on an unaudited pro forma financial basis presents the combined results of j2 Global and its 2016 acquisitions as if each acquisition had occurred on January 1, 2015 (in thousands, except per share amounts): Year ended December 31, 2016 December 31, 2015 (unaudited) (unaudited) Revenues $ 1,102,510 $ 1,009,169 Net income $ 108,822 $ 111,817 EPS - Basic $ 2.25 $ 2.31 EPS - Diluted $ 2.24 $ 2.29 The supplemental information on an unaudited pro forma financial basis presents the combined results of j2 Global and its 2015 acquisitions as if each acquisition had occurred on January 1, 2014 (in thousands, except per share amounts): Year ended December 31, 2015 December 31, 2014 (unaudited) (unaudited) Revenues $ 823,904 $ 744,388 Net income $ 159,408 $ 126,196 EPS - Basic $ 3.29 $ 2.64 EPS - Diluted $ 3.26 $ 2.62
EVDY [Member]
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The following table summarizes the allocation of the purchase consideration for the Everyday Health acquisition (in thousands): Assets and Liabilities Valuation Cash $ 15,918 Accounts receivable 67,968 Other assets 11,168 Property and equipment 6,494 Trademarks 70,300 Customer relationships 45,500 Other intangibles 88,267 Goodwill 263,988 Accounts payables and accrued expenses (59,091 ) Deferred revenue (5,297 ) Deferred tax liability (11,500 ) Total $ 493,715
Business Acquisition, Pro Forma Information [Table Text Block]	The supplemental information on an unaudited pro forma financial basis presents the combined results of j2 Global and Everyday Health as if the acquisition had occurred on January 1, 2015 (in thousands, except per share amounts): Year ended December 31, 2016 December 31, 2015 (unaudited) (unaudited) Revenues $ 1,082,813 $ 952,806 Net income $ 103,541 $ 115,059 EPS - Basic $ 2.14 $ 2.38 EPS - Diluted $ 2.13 $ 2.35

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2017
Investments [Abstract]
Marketable Securities [Table Text Block]	The following table summarizes the Company’s investments (in thousands): December 31, December 31, 2016 Certificates of deposit $ — $ 60 Equity securities 57,722 — Total $ 57,722 $ 60

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Schedule Of Fair Values Of Financial Instruments Measured On Recurring Basis	The following tables present the fair values of the Company’s financial assets or liabilities that are measured at fair value on a recurring basis (in thousands): December 31, 2017 Level 1 Level 2 Level 3 Fair Value Assets: Cash equivalents: Money market and other funds $ 453 $ — $ — $ 453 Total assets measured at fair value $ 453 $ — $ — $ 453 Liabilities: Contingent consideration $ — $ — $ 20,477 $ 20,477 Contingent interest derivative — 768 — 768 Total liabilities measured at fair value $ — $ 768 $ 20,477 $ 21,245 December 31, 2016 Level 1 Level 2 Level 3 Fair Value Assets: Cash equivalents: Money market and other funds $ 7,737 $ — $ — $ 7,737 Certificates of Deposit — 60 — 60 Total assets measured at fair value $ 7,737 $ 60 $ — $ 7,797 Liabilities: Contingent consideration $ — $ — $ 17,450 $ 17,450 Contingent interest derivative — 958 — 958 Total liabilities measured at fair value $ — $ 958 $ 17,450 $ 18,408
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents a reconciliation of the Company’s derivative instruments (in thousands): Amount Affected line item in the Statement of Income Derivative Liabilities: Level 2: Balance as of January 1, 2016 $ 1,450 Total fair value adjustments reported in earnings (492 ) Interest expense, net Balance as of December 31, 2016 $ 958 Total fair value adjustments reported in earnings (190 ) Interest expense, net Balance as of December 31, 2017 $ 768
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	The following tables presents a reconciliation of the Company’s Level 3 financial assets or liabilities that are measured at fair value on a recurring basis (in thousands): Level 3 Affected line item in the Statement of Income Balance as of January 1, 2016 $ 30,600 Total fair value adjustments reported in earnings 4,850 General and administrative Contingent consideration payments (18,000 ) Not Applicable Balance as of December 31, 2016 $ 17,450 Contingent consideration 17,577 Total fair value adjustments reported in earnings 2,300 General and administrative Contingent consideration payments (16,850 ) Not Applicable Balance as of December 31, 2017 $ 20,477

Property And Equipment (Tables)

Property And Equipment (Tables)	12 Months Ended
	Dec. 31, 2017
Property And Equipment [Abstract]
Property, Plant and Equipment	Property and equipment, stated at cost, at December 31, 2017 and 2016 consisted of the following (in thousands): 2017 2016 Computers and related equipment $ 215,631 $ 173,103 Furniture and equipment 2,035 1,928 Leasehold improvements 16,163 12,929 233,829 187,960 Less: Accumulated depreciation and amortization (154,056 ) (119,866 ) Total property and equipment, net $ 79,773 $ 68,094

Goodwill And Intangible Assets

Goodwill And Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Changes In Carrying Amounts Of Goodwill	The changes in carrying amounts of goodwill for the years ended December 31, 2017 and 2016 are as follows (in thousands): Cloud Services Digital Media Consolidated Balance as of January 1, 2016 $ 502,718 $ 304,943 $ 807,661 Goodwill acquired (Note 3) 69,202 263,988 333,190 Purchase Accounting Adjustments (4) 816 (4,957 ) (4,141 ) Foreign exchange translation (13,584 ) (316 ) (13,900 ) Balance as of December 31, 2016 $ 559,152 $ 563,658 $ 1,122,810 Goodwill acquired (Note 3) 34,035 87,792 121,827 Goodwill written off related to sale of a business unit (1)(2)(3) (3,614 ) (54,127 ) (57,741 ) Purchase accounting adjustments (4) (766 ) (4,667 ) (5,433 ) Foreign exchange translation 14,946 202 15,148 Balance as of December 31, 2017 $ 603,753 $ 592,858 $ 1,196,611
Schedule Of Intangible Assets With Indefinite Lives	Intangible Assets with Indefinite Lives: 2017 2016 Trade names $ 27,379 $ 27,379 Other 5,432 5,432 Total $ 32,811 $ 32,811
Finite-Lived Intangible Assets By Major Class	Intangible Assets Subject to Amortization: As of December 31, 2017 , intangible assets subject to amortization relate primarily to the following (in thousands): Weighted-Average Amortization Period Historical Cost Accumulated Amortization Net Trade names 11.2 years $ 147,997 $ 51,429 $ 96,568 Patent and patent licenses 6.6 years 67,724 56,853 10,871 Customer relationships (1) 8.9 years 447,070 253,464 193,606 Other purchased intangibles 4.8 years 218,628 66,733 151,895 Total $ 881,419 $ 428,479 $ 452,940 (1) Historically, the Company has amortized its customer relationship assets in a pattern that best reflects the pace in which the assets’ benefits are consumed. This pattern results in a substantial majority of the amortization expense being recognized in the first four to five years, despite the overall life of the asset. As of December 31, 2016 , intangible assets subject to amortization relate primarily to the following (in thousands): Weighted-Average Amortization Period Historical Cost Accumulated Amortization Net Trade names 11.5 years $ 127,342 $ 38,868 $ 88,474 Patent and patent licenses 6.6 years 65,605 51,677 13,928 Customer relationships (1) 9.6 years 390,930 182,775 208,155 Other purchased intangibles 6.0 years 195,913 27,590 168,323 Total $ 779,790 $ 300,910 $ 478,880 (1) Historically, the Company has amortized its customer relationship assets in a pattern that best reflects the pace in which the assets’ benefits are consumed. This pattern results in a substantial majority of the amortization expense being recognized in the first four to five years, despite the overall life of the asset. During the year ended December 31, 2016 , the Company acquired Everyday Health. The identified intangible assets recognized as part of the acquisition and their respective estimated weighted average amortizations were as follows (in thousands): December 31, 2016 Weighted-Average Amortization Period Fair Value Trademarks 5.2 years $ 70,300 Customer relationships 10.1 years 45,500 Other purchased intangibles 1.7 years 88,267 Total $ 204,067 During the year ended December 31, 2016 , the Company completed 21 other acquisitions which were individually immaterial. The identified intangible assets recognized as part of these acquisition and their respective estimated weighted average amortizations were as follows (in thousands): December 31, 2016 Weighted-Average Amortization Period Fair Value Trade names 6.3 years $ 5,866 Customer relationships 7.5 years 39,982 Other purchased intangibles 3.3 years 2,997 Total $ 48,845
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	Expected amortization expenses for intangible assets subject to amortization at December 31, 2017 are as follows (in thousands): Fiscal Year: 2018 $ 122,294 2019 103,172 2020 54,315 2021 35,280 2022 30,231 Thereafter 107,648 Total expected amortization expense $ 452,940

Long Term Debt (Tables)

Long Term Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Long-term Debt, Unclassified [Abstract]
Convertible Debt [Table Text Block]	The following table provides additional information related to our Convertible Notes (in thousands): 2017 2016 Additional paid-in capital $ 37,700 $ 37,700 Principal amount of Convertible Notes $ 402,500 $ 402,500 Unamortized discount of the liability component 32,189 40,356 Carrying amount of debt issuance costs 5,667 7,002 Net carrying amount of Convertible Notes $ 364,644 $ 355,142
Interest Expense Related To Convertible Notes [Table Text Block]	The following table provides the components of interest expense related to our Convertible Notes (in thousands): 2017 2016 2015 Cash interest expense (coupon interest expense) $ 13,081 $ 13,081 $ 13,081 Non-cash amortization of discount on Convertible Notes 8,167 7,707 7,274 Amortization of debt issuance costs 1,335 1,217 1,109 Total interest expense related to Convertible Notes $ 22,583 $ 22,005 $ 21,464
Schedule of Long-term Debt Instruments [Table Text Block]	Long-term debt as of December 31, 2017 and 2016 consists of the following (in thousands): 2017 2016 Senior Notes: 6.0% Senior Notes $ 650,000 $ — 8.0% Senior Notes — 250,000 3.25% Convertible Notes 402,500 402,500 Less: Unamortized discount (42,902 ) (42,997 ) Deferred issuance costs (7,654 ) (7,757 ) Total long-term debt $ 1,001,944 $ 601,746 Less: Current portion — — Total long-term debt, less current portion $ 1,001,944 $ 601,746
Schedule of Maturities of Long-term Debt [Table Text Block]	At December 31, 2017 , future principal payments for debt were as follows (in thousands): Years Ended December 31, 2018 $ — 2019 — 2020 — 2021 402,500 2022 — Thereafter 650,000 $ 1,052,500

Commitments And Contingencies C

Commitments And Contingencies Commitments And Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]	j2 Global leases certain facilities and equipment under non-cancelable operating leases which expire at various dates through 2025. Office and equipment leases are typically for terms of three to five years and generally provide renewal options for terms up to an additional five years. In most cases, the Company expects leases that expire will be renewed or replaced by other leases with similar terms. Future minimum lease payments at December 31, 2017 under non-cancelable operating leases (with initial or remaining lease terms in excess of one year) are as follows (in thousands): Lease Payments Fiscal Year: 2018 $ 18,589 2019 17,325 2020 13,721 2021 12,049 2022 11,199 Thereafter 13,258 Total minimum lease payments $ 86,141

Income Taxes Income Taxes (Tabl

Income Taxes Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Taxes [Abstract]
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	The provision for income tax consisted of the following (in thousands): Years Ended December 31, 2017 2016 2015 Current: Federal $ 55,804 $ 46,293 $ 21,745 State 3,265 3,874 1,805 Foreign 22,904 22,612 16,816 Total current 81,973 72,779 40,366 Deferred: Federal (15,682 ) (6,822 ) (8,581 ) State 962 (330 ) (3,462 ) Foreign (6,712 ) (6,627 ) (5,040 ) Total deferred (21,432 ) (13,779 ) (17,083 ) Total provision $ 60,541 $ 59,000 $ 23,283
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	A reconciliation of the statutory federal income tax rate with j2 Global’s effective income tax rate is as follows: Years Ended December 31, 2017 2016 2015 Statutory tax rate 35 % 35 % 35 % State income taxes, net 0.8 1.1 0.3 Foreign rate differential (16.1 ) (14.6 ) (15.8 ) Foreign income inclusion 7.2 9.4 5.4 Foreign tax credit (6.2 ) (5.5 ) (6.1 ) Reserve for uncertain tax positions 3.9 4.7 (3.3 ) Valuation allowance (0.9 ) (1.0 ) 1.8 IRC Section 199 deductions (1.6 ) (1.1 ) (1.2 ) The 2017 Tax Act - provisional transition tax 24.6 — — The 2017 Tax Act - tax rate impact on deferred taxes (16.1 ) — — Other (0.3 ) (0.1 ) (1.3 ) Effective tax rates 30.3 % 27.9 % 14.8 %
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	Deferred tax assets and liabilities result from differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities. Temporary differences and carryforwards which give rise to deferred tax assets and liabilities are as follows (in thousands): Years Ended December 31, 2017 2016 Deferred tax assets: Net operating loss carryforwards $ 29,317 $ 59,806 Tax credit carryforwards 2,645 16,281 Accrued expenses 3,165 14,759 Allowance for bad debt 1,570 2,624 Share-based compensation expense 6,476 5,631 Basis difference in fixed assets 1,881 2,195 Impairment of investments 48 74 Deferred revenue 728 2,361 State taxes 1,777 1,758 Other 14,165 9,227 61,772 114,716 Less: valuation allowance (197 ) (12,028 ) Total deferred tax assets $ 61,575 $ 102,688 Deferred tax liabilities: Basis difference in intangible assets $ (70,252 ) $ (98,830 ) Prepaid insurance (616 ) (246 ) Convertible debt (27,504 ) (36,592 ) Other (1,467 ) (2,088 ) Total deferred tax liabilities (99,839 ) (137,756 ) Net deferred tax liabilities $ (38,264 ) $ (35,068 )
Summary of Income Tax Contingencies [Table Text Block]	The aggregate changes in the balance of unrecognized tax benefits, which excludes interest and penalties, for 2017 , 2016 and 2015 , is as follows (in thousands): Years Ended December 31, 2017 2016 2015 Beginning balance $ 41,218 $ 32,536 $ 34,635 Increases related to tax positions during a prior year — 2,082 10,361 Decreases related to tax positions taken during a prior year (401 ) — (17,107 ) Increases related to tax positions taken in the current year 7,223 6,703 8,841 Settlements (2,639 ) — (4,194 ) Decreases related to expiration of statute of limitations (389 ) (103 ) — Ending balance $ 45,012 $ 41,218 $ 32,536

Stockholders' Equity Dividends

Stockholders' Equity Dividends Declared (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Dividends Declared [Table Text Block]	The following is a summary of each dividend declared during fiscal year 2017 and 2016: Declaration Date Dividend per Common Share Record Date Payment Date February 10, 2016 $ 0.3250 February 23, 2016 March 10, 2016 May 5, 2016 $ 0.3350 May 18, 2016 June 2, 2016 August 2, 2016 $ 0.3450 August 17, 2016 September 1, 2016 November 1, 2016 $ 0.3550 November 18, 2016 December 5, 2016 February 9, 2017 $ 0.3650 February 22, 2017 March 9, 2017 May 4, 2017 $ 0.3750 May 19, 2017 June 2, 2017 August 2, 2017 $ 0.3850 August 14, 2017 September 1, 2017 October 31, 2017 $ 0.3950 November 17, 2017 December 5, 2017

Stock Options And Employee St39

Stock Options And Employee Stock Purchase Plan (Tables)	12 Months Ended
	Dec. 31, 2017
Stock Options Activity	Stock option activity for the years ended December 31, 2017 , 2016 and 2015 is summarized as follows: Number of Shares Weighted-Average Exercise Price Weighted-Average Remaining Contractual Life (In Years) Aggregate Intrinsic Value Options outstanding at January 1, 2015 725,649 $ 24.29 Granted 62,000 67.35 Exercised (221,221 ) 22.41 Canceled — — Options outstanding at December 31, 2015 566,428 $ 29.74 Granted — — Exercised (142,870 ) 26.04 Canceled (9,700 ) 26.92 Options outstanding at December 31, 2016 413,858 $ 31.09 Granted — — Exercised (38,183 ) 29.03 Canceled — — Options outstanding at December 31, 2017 375,675 $ 31.30 2.5 $16,429,727 Exercisable at December 31, 2017 361,875 $ 29.92 2.3 $16,323,743 Vested and expected to vest at December 31, 2017 373,168 $ 31.05 2.4 $16,410,477
Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range	The following table summarizes information concerning outstanding and exercisable options as of December 31, 2017 : Options Outstanding Exercisable Options Range of Exercise Prices Number Outstanding December 31, 2017 Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number Exercisable December 31, 2017 Weighted Average Exercise Price $17.19 22,000 1.18 years $ 17.19 22,000 $ 17.19 20.91 45,558 0.34 years 20.91 45,558 20.91 21.67 50,040 1.35 years 21.67 50,040 21.67 22.92 84,092 2.35 years 22.92 84,092 22.92 24.61 - 25.93 14,500 4.02 years 25.13 14,500 25.13 27.60 700 3.08 years 27.60 700 27.60 29.34 75,585 3.36 years 29.34 75,585 29.34 29.53 13,700 4.17 years 29.53 13,700 29.53 31.07 7,500 3.82 years 31.07 7,500 31.07 67.35 62,000 3.51 years 67.35 48,200 67.35 $17.19 - $67.35 375,675 2.46 years $ 31.30 361,875 $ 29.92
Assumptions To Estimate Fair Value Of Stock Options	The weighted-average fair values of stock options granted have been estimated utilizing the following assumptions: Years Ended December 31, 2017 2016 2015 Risk-free interest rate —% —% 1.6% Expected term (in years) 0.0 0.0 5.2 Dividend yield —% —% 1.8% Expected volatility —% —% 28.1% Weighted average volatility —% —% 28.1%
Restricted (Performance) Stock [Member]
Schedule of Share-based Payment Award, Performance Awards, Valuation Assumptions	The weighted-average fair values of market-based restricted stock awards granted have been estimated utilizing the following assumptions: December 31, 2017 December 31, 2016 Underlying stock price at valuation date $ 91.17 $ 63.73 Expected volatility 29.0 % 29.8 % Risk-free interest rate 2.17 % 1.51 %
Restricted Stock [Member]
Restricted Stock And Restricted Stock Unit Award Activity	Restricted stock award activity for the years ended December 31, 2017 , 2016 and 2015 is set forth below: Shares Weighted-Average Grant-Date Fair Value Nonvested at January 1, 2015 814,050 $ 26.57 Granted 234,540 68.11 Vested (254,871 ) 25.16 Canceled (88,915 ) 40.97 Nonvested at December 31, 2015 704,804 $ 39.08 Granted 296,414 41.27 Vested (255,503 ) 31.27 Canceled (40,700 ) 63.95 Nonvested at December 31, 2016 705,015 $ 41.40 Granted 289,230 61.34 Vested (381,411 ) 39.71 Canceled (7,268 ) 76.08 Nonvested at December 31, 2017 605,566 $ 51.57
Restricted Stock Units (RSUs) [Member]
Restricted Stock And Restricted Stock Unit Award Activity	Restricted stock unit activity for the years ended December 31, 2017 , 2016 and 2015 is set forth below: Number of Weighted-Average Aggregate Outstanding at January 1, 2015 102,924 Granted 18,400 Vested (23,221 ) Canceled (41,858 ) Outstanding at December 31, 2015 56,245 Granted 21,500 Vested (14,595 ) Canceled (11,200 ) Outstanding at December 31, 2016 51,950 Granted 11,100 Vested (16,370 ) Canceled (8,280 ) Outstanding at December 31, 2017 38,400 1.8 $ 2,881,152 Vested and expected to vest at December 31, 2017 29,397 1.6 $ 2,205,686

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share Reconciliation [Abstract]
Components Of Basic And Diluted Earnings Per Share	The components of basic and diluted earnings per share are as follows (in thousands, except share and per share data): Years Ended December 31, 2017 2016 2015 Numerator for basic and diluted net income per common share: Net income attributable to j2 Global, Inc. common shareholders $ 139,425 $ 152,439 $ 133,636 Net income available to participating securities (a) (1,792 ) (2,242 ) (2,159 ) Net income available to j2 Global, Inc. common shareholders 137,633 150,197 131,477 Denominator: Weighted-average outstanding shares of common stock 47,586,242 47,668,357 47,627,853 Dilutive effect of: Equity incentive plans 228,166 201,660 293,911 Convertible debt (b) 854,619 93,209 165,996 Common stock and common stock equivalents 48,669,027 47,963,226 48,087,760 Net income per share: Basic $ 2.89 $ 3.15 $ 2.76 Diluted $ 2.83 $ 3.13 $ 2.73 (a) Represents unvested share-based payment awards that contain certain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). (b) Represents the incremental shares issuable upon conversion of the Convertible Notes due June 15, 2029 by applying the treasury stock method when the average stock price exceeds the conversion price of the Convertible Notes (see Note 9 - Long Term Debt)

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segments, Geographical Areas [Abstract]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated	Information on reportable segments and reconciliation to consolidated income from operations is as follows (in thousands): Years Ended December 31, 2017 2016 2015 Revenue by segment: Cloud Services $ 578,956 $ 566,938 $ 504,638 Digital Media 538,939 307,463 216,374 Elimination of inter-segment revenues (57 ) (146 ) (197 ) Total revenue 1,117,838 874,255 720,815 Direct costs by segment (1) : Cloud Services 352,912 356,059 294,436 Digital Media 490,871 256,763 185,937 Direct costs by segment (1) : 843,783 612,822 480,373 Cloud Services operating income (2) 226,044 210,879 210,202 Digital Media operating income 48,068 50,700 30,437 Segment operating income 274,112 261,579 240,639 Global operating costs (2)(3) 28,404 19,013 41,257 Income from operations $ 245,708 $ 242,566 $ 199,382 (1) Direct costs for each segment include cost of revenues and other operating expenses that are directly attributable to the segment, such as employee compensation expense, local sales and marketing expenses, engineering and network operations expenses, depreciation and amortization and other administrative expenses. (2) During 2016, the Company determined certain personnel and third-party costs were directly attributable to a particular segment. As a result, these costs were no longer classified as Global operating costs in 2016. If such costs in 2015 were classified consistent with the 2016 presentation, the operating income for Cloud Services segment would have been $189.1 million and Global operating costs would have been $20.2 million, respectively. (3) Global operating costs include general and administrative and other corporate expenses that are managed on a global basis and that are not directly attributable to any particular segment.
Schedule of Segment Reporting Information, by Segment	2017 2016 Assets: Cloud Services $ 1,078,577 $ 911,327 Digital Media 1,317,113 1,124,535 Total assets from reportable segments 2,395,690 2,035,862 Corporate 57,403 26,466 Total assets $ 2,453,093 $ 2,062,328 2017 2016 2015 Capital expenditures: Cloud Services $ 7,031 $ 6,113 $ 7,546 Digital Media 32,564 18,633 9,389 Total from reportable segments 39,595 24,746 16,935 Corporate — — 362 Total capital expenditures $ 39,595 $ 24,746 $ 17,297 Depreciation and amortization: Cloud Services $ 68,436 $ 79,533 $ 62,385 Digital Media 93,605 42,558 30,008 Total from reportable segments 162,041 122,091 92,393 Corporate — — 820 Total depreciation and amortization $ 162,041 $ 122,091 $ 93,213
Summary On Revenues And Long-Lived Assets By Geographic Areas	j2 Global maintains operations in the U.S., Canada, Ireland, Japan and other countries. Geographic information about the U.S. and all other countries for the reporting periods is presented below. Such information attributes revenues based on jurisdictions where revenues are reported (in thousands). Years Ended December 31, 2017 2016 2015 Revenues: United States $ 830,800 $ 607,285 $ 492,682 Canada 78,099 76,775 74,864 Ireland 74,430 71,340 43,717 All other countries 134,509 118,855 109,552 Total $ 1,117,838 $ 874,255 $ 720,815 December 31, December 31, Long-lived assets: United States $ 452,143 $ 453,053 All other countries 80,571 93,430 Total $ 532,714 $ 546,483

Accumulated Other Comprehensi42

Accumulated Other Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2017
Accumulated Other Comprehensive Income [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table summarizes the changes in accumulated balances of other comprehensive income, net of tax, for the years ended December 31, 2017 and 2016 (in thousands): Unrealized Gains (Losses) on Investments Foreign Currency Translation Total Balance as of January 1, 2016 $ 2,449 $ (31,573 ) $ (29,124 ) Other comprehensive income (loss) before reclassifications 744 (23,076 ) (22,332 ) Amounts reclassified from accumulated other comprehensive income (3,193 ) — (3,193 ) Net current period other comprehensive loss (2,449 ) (23,076 ) (25,525 ) Balance as of December 31, 2016 $ — $ (54,649 ) $ (54,649 ) Other comprehensive income before reclassifications — 25,559 25,559 Net current period other comprehensive income — 25,559 25,559 Balance as of December 31, 2017 $ — $ (29,090 ) $ (29,090 )
Reclassification out of Accumulated Other Comprehensive Income	The following table provides details about reclassifications out of accumulated other comprehensive income for the years ended December 31, 2017 and 2016 (in thousands): Details about Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income Year Ended December 31, 2017 Year Ended December 31, 2016 Unrealized gain on available-for-sale investments $ — $ (5,149 ) Other (income) expense, net — (5,149 ) Income before income taxes — 1,956 Income tax expense — (3,193 ) Net income Total reclassifications for the period $ — $ (3,193 ) Net income

Quarterly Results (Tables)

Quarterly Results (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Results [Abstract]
Schedule of Quarterly Financial Information	Year Ended December 31, 2017 Fourth Quarter Third Quarter Second Quarter First Quarter Revenues $ 316,380 $ 273,616 $ 273,174 $ 254,669 Gross profit 270,406 231,245 230,015 213,859 Net income 49,871 32,358 31,376 25,820 Net income per common share: Basic $ 1.03 $ 0.67 $ 0.65 $ 0.54 Diluted $ 1.02 $ 0.66 $ 0.63 $ 0.52 Weighted average shares outstanding Basic 47,721,700 47,609,819 47,547,118 47,463,231 Diluted 48,437,580 48,521,082 48,948,315 48,766,031 Year Ended December 31, 2016 Fourth Third Second First Revenues $ 251,837 $ 210,116 $ 211,800 $ 200,502 Gross profit 211,608 173,124 176,209 166,214 Net income 43,158 45,569 33,770 29,943 Net income per common share: Basic $ 0.90 $ 0.95 $ 0.69 $ 0.62 Diluted $ 0.89 $ 0.94 $ 0.69 $ 0.61 Weighted average shares outstanding Basic 47,348,372 47,310,011 48,055,783 47,966,718 Diluted 47,862,218 47,494,744 48,265,298 48,238,098

Basis Of Presentation (Details)

Basis Of Presentation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	$ 25,559	$ (23,076)	$ (15,058)
Foreign Currency Transaction Gain (Loss), Realized	(5,800)	(700)	(100)
Advertising Expense	143,300	$ 96,800	$ 63,500
Operating Leases, Future Minimum Payments Due	86,141
Excess Tax Benefit from Share-based Compensation, Operating Activities	$ 2,300
Minimum [Member]
Property, Plant and Equipment, Useful Life	1 year
Identifiable intangible assets minimum useful life (years)	1 year
Maximum [Member]
Property, Plant and Equipment, Useful Life	10 years
Identifiable intangible assets minimum useful life (years)	20 years
Property, Plant and Equipment, Other Types [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life	1 year
Property, Plant and Equipment, Other Types [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life	5 years

Business Acquisition Business A

Business Acquisition Business Acquisition (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition Contributed Total Revenue	$ 34,700	$ 52,900	$ 52,400
Business Combination, Consideration Transferred	203,922	596,074	314,019
Purchase Accounting Adjustments (4)	$ 5,433	(4,141)
Stock Repurchased During Period, Shares	2,100,000
Goodwill acquired (Note 3)	$ 121,827	333,190	172,593
Business Acquisition, Purchase Price Allocation, Goodwill, Expected Tax Deductible Amount	$ 34,700	$ 102,400	$ 143,300
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
IGC [Member]
Business Combination, Consideration Transferred		$ 6,300
Stock Repurchased During Period, Shares		935,231
Business Acquisition, Date of Acquisition Agreement		Jul. 12, 2016
Stock Repurchased During Period, Value		$ 51,500
EVDY [Member]
Business Acquisition Contributed Total Revenue		23,200
Business Combination, Consideration Transferred		493,715
Goodwill acquired (Note 3)		263,988
Business Acquisition, Purchase Price Allocation, Goodwill, Expected Tax Deductible Amount		$ 65,400
Common stock, par value (in dollars per share)		$ 0.01
Business Acquisition, Share Price		$ 10.50
Cloud Services
Purchase Accounting Adjustments (4)	$ (766)	$ 816
Goodwill acquired (Note 3)	34,035	69,202
Digital Media
Purchase Accounting Adjustments (4)	4,667	4,957
Goodwill acquired (Note 3)	$ 87,792	$ 263,988

Business Acquisition Business46

Business Acquisition Business Acquisitions (Allocation Of Aggregate Purchase Price) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Accounts receivable	$ 14,130	$ 70,922	$ 14,935
Other assets	10,243	11,730	1,415
Property and equipment	6,411	11,109	5,769
Deferred tax asset	405
Goodwill	121,827	333,190	172,593
Accounts payables and accrued expenses	(27,995)	(62,188)	(9,684)
Deferred revenue	(11,853)	(6,904)	(10,764)
Deferred tax liability	(29,534)	(14,503)	(1,316)
Capital lease		(194)	(195)
Total	203,922	596,074	314,019
Developed Technology Rights [Member]
Business Acquisition [Line Items]
Intangible assets			18,764
Trade names
Business Acquisition [Line Items]
Intangible assets	20,610	5,866	22,602
Trademarks
Business Acquisition [Line Items]
Intangible assets	1,373	70,300
Customer relationships
Business Acquisition [Line Items]
Intangible assets	61,307	85,482	98,027
Other purchased intangibles
Business Acquisition [Line Items]
Intangible assets	36,998	91,264	$ 1,873
Digital Media
Business Acquisition [Line Items]
Goodwill	$ 87,792	263,988
EVDY [Member]
Business Acquisition [Line Items]
Cash		15,918
Accounts receivable		67,968
Other assets		11,168
Property and equipment		6,494
Intangible assets		204,067
Goodwill		263,988
Accounts payables and accrued expenses		(59,091)
Deferred revenue		(5,297)
Deferred tax liability		(11,500)
Total		493,715
EVDY [Member] | Trademarks
Business Acquisition [Line Items]
Intangible assets		70,300
EVDY [Member] | Customer relationships
Business Acquisition [Line Items]
Intangible assets		45,500
EVDY [Member] | Other purchased intangibles
Business Acquisition [Line Items]
Intangible assets		$ 88,267

Business Acquisition Business47

Business Acquisition Business Acquisitions (Supplementary Information On Unaudited Pro Forma Financial Results Of Acquisition) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
EVDY [Member]
Business Acquisition, Pro Forma Revenue	$ 1,082,813	$ 952,806
Business Acquisition, Pro Forma Net Income (Loss)	$ 103,541	$ 115,059
Business Acquisition, Pro Forma Earnings Per Share, Basic	$ 2.14	$ 2.38
Business Acquisition, Pro Forma Earnings Per Share, Diluted	$ 2.13	$ 2.35
2016 Business Acquisition [Member]
Business Acquisition, Pro Forma Revenue	$ 1,102,510	$ 1,009,169
Business Acquisition, Pro Forma Net Income (Loss)	$ 108,822	$ 111,817
Business Acquisition, Pro Forma Earnings Per Share, Basic	$ 2.25	$ 2.31
Business Acquisition, Pro Forma Earnings Per Share, Diluted	$ 2.24	$ 2.29
2015 Business Acquisition [Member]
Business Acquisition, Pro Forma Revenue		$ 823,904	$ 744,388
Business Acquisition, Pro Forma Net Income (Loss)		$ 159,408	$ 126,196
Business Acquisition, Pro Forma Earnings Per Share, Basic		$ 3.29	$ 2.64
Business Acquisition, Pro Forma Earnings Per Share, Diluted		$ 3.26	$ 2.62

Investments (Narrative) (Detail

Investments (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Gain on available-for-sale investments	$ 0	$ 7,716	$ 549

Investments (Schedule Of Availa

Investments (Schedule Of Available-For-Sale And Trading Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investments [Abstract]
Certificates of Deposit, at Carrying Value	$ 0	$ 60
Other Investments and Securities, at Cost	57,722	0
Investments	$ 57,722	$ 60

Assets Held for Sale (Details)

Assets Held for Sale (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Digital Media | Tea Leaves [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	$ 27
Digital Media | Cambridge [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	0.9
Cloud Services [Member] | Web24 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	$ 1.6

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt, Fair Value	$ 1,188,700	$ 792,200
Contingent consideration	20,477	17,450
Other Payments to Acquire Businesses		20,000
Ookla [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		40,000
Contingent consideration		17,000
Other Payments to Acquire Businesses		16,900
Payments to Employees		3,100
Salesify [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	17,000
Contingent consideration	0	600
Humble Bundle [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	40,000
Contingent consideration	19,700
Black Friday [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	1,500
Contingent consideration	800
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contingent consideration	20,477	17,450	$ 30,600
Other Payments to Acquire Businesses	16,850
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	$ 2,300	$ 4,850

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule Of Fair Values Of Financial Instruments Measured On Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Total assets measured at fair value	$ 453	$ 7,797
Contingent consideration	20,477	17,450
Contingent interest derivative	768	958
Total liabilities measured at fair value	21,245	18,408
Certificates of Deposit [Member]
Investments		60
Money Market Funds [Member]
Cash	453	7,737
Level 1
Total assets measured at fair value	453	7,737
Contingent consideration	0	0
Contingent interest derivative	0	0
Total liabilities measured at fair value	0	0
Level 1 | Certificates of Deposit [Member]
Investments		0
Level 1 | Money Market Funds [Member]
Cash	453	7,737
Level 2
Total assets measured at fair value	0	60
Contingent consideration	0	0
Contingent interest derivative	768	958	$ 1,450
Total liabilities measured at fair value	768	958
Level 2 | Certificates of Deposit [Member]
Investments		60
Level 2 | Money Market Funds [Member]
Cash	0	0
Level 3
Total assets measured at fair value	0	0
Contingent consideration	20,477	17,450	$ 30,600
Contingent interest derivative	0	0
Total liabilities measured at fair value	20,477	17,450
Level 3 | Certificates of Deposit [Member]
Investments		0
Level 3 | Money Market Funds [Member]
Cash	$ 0	$ 0

Fair Value Measurements (Sche53

Fair Value Measurements (Schedule of Changes In Fair Value Of Level 3 Financial Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 17,450
Contingent consideration payments		$ (20,000)
Ending balance	20,477	17,450
Level 3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	17,450	30,600
Contingent consideration	17,577
Total fair value adjustments reported in earnings	2,300	4,850
Contingent consideration payments	(16,850)
Ending balance	$ 20,477	17,450
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Transfers, Net		$ (18,000)

Fair Value Measurements (Deriva

Fair Value Measurements (Derivative Summary) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 958
Total fair value adjustments reported in earnings	(200)	$ (500)	$ 700
Ending balance	768	958
Level 2
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	958	1,450
Total fair value adjustments reported in earnings	(190)	(492)
Ending balance	$ 768	$ 958	$ 1,450

Property And Equipment (Propert

Property And Equipment (Property And Equipment) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 233,829	$ 187,960
Less: Accumulated depreciation and amortization	(154,056)	(119,866)
Total property and equipment, net	79,773	68,094
Computers and related equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	215,631	173,103
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,035	1,928
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 16,163	$ 12,929

Property And Equipment (Narrati

Property And Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property And Equipment [Abstract]
Depreciation	$ 33	$ 26.8	$ 19.2
Property, Plant and Equipment, Disposals	$ 4	$ 0	$ 0

Goodwill And Intangible Asset57

Goodwill And Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 129	$ 95.3	$ 74
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets minimum useful life (years)	1 year
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets minimum useful life (years)	20 years

Goodwill And Intangible Asset58

Goodwill And Intangible Assets (Changes In Carrying Amounts Of Goodwill And Other Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Beginning balance	$ 1,122,810	$ 807,661
Goodwill acquired (Note 3)	121,827	333,190	$ 172,593
Goodwill, Written off Related to Sale of Business Unit	(57,741)
Purchase Accounting Adjustments (4)	5,433	(4,141)
Foreign exchange translation	15,148	13,900
Ending balance	1,196,611	1,122,810	807,661
Cloud Services
Goodwill [Roll Forward]
Beginning balance	559,152	502,718
Goodwill acquired (Note 3)	34,035	69,202
Goodwill, Written off Related to Sale of Business Unit	(3,614)
Purchase Accounting Adjustments (4)	(766)	816
Foreign exchange translation	14,946	13,584
Ending balance	603,753	559,152	502,718
Digital Media
Goodwill [Roll Forward]
Beginning balance	563,658	304,943
Goodwill acquired (Note 3)	87,792	263,988
Goodwill, Written off Related to Sale of Business Unit	(54,127)
Purchase Accounting Adjustments (4)	4,667	4,957
Foreign exchange translation	202	316
Ending balance	592,858	$ 563,658	$ 304,943
Cambridge [Member] | Digital Media
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(17,800)
Web24 [Member] | Cloud Services [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(3,600)
Tea Leaves [Member] | Digital Media
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	$ (36,300)

Goodwill And Intangible Asset59

Goodwill And Intangible Assets (Indefinite Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Intangible assets	$ 32,811	$ 32,811
Trade names
Intangible assets	27,379	27,379
Other
Intangible assets	$ 5,432	$ 5,432

Goodwill And Intangible Asset60

Goodwill And Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Historical Cost	$ 881,419	$ 779,790
Accumulated Amortization	(428,479)	(300,910)
Net	$ 452,940	$ 478,880
Trade names
Weighted-Average Amortization Period, years	11 years 2 months 12 days	11 years 6 months
Historical Cost	$ 147,997	$ 127,342
Accumulated Amortization	(51,429)	(38,868)
Net	96,568	88,474
Fair Value	$ 20,610	$ 5,866	$ 22,602
Patent and patent licenses
Weighted-Average Amortization Period, years	6 years 7 months 6 days	6 years 7 months 6 days
Historical Cost	$ 67,724	$ 65,605
Accumulated Amortization	(56,853)	(51,677)
Net	$ 10,871	$ 13,928
Customer relationships
Weighted-Average Amortization Period, years	8 years 10 months 24 days	9 years 7 months 6 days
Historical Cost	$ 447,070	$ 390,930
Accumulated Amortization	(253,464)	(182,775)
Net	193,606	208,155
Fair Value	$ 61,307	$ 85,482	98,027
Other purchased intangibles
Weighted-Average Amortization Period, years	4 years 9 months 18 days	6 years
Historical Cost	$ 218,628	$ 195,913
Accumulated Amortization	(66,733)	(27,590)
Net	151,895	168,323
Fair Value	36,998	91,264	$ 1,873
Trademarks
Fair Value	$ 1,373	70,300
EVDY [Member]
Fair Value		$ 204,067
EVDY [Member] | Customer relationships
Weighted-Average Amortization Period		10 years 1 month 6 days
Fair Value		$ 45,500
EVDY [Member] | Other purchased intangibles
Weighted-Average Amortization Period		1 year 8 months 12 days
Fair Value		$ 88,267
EVDY [Member] | Trademarks
Weighted-Average Amortization Period		5 years 2 months 12 days
Fair Value		$ 70,300
2016 Business Acquisition [Member]
Fair Value		$ 48,845
2016 Business Acquisition [Member] | Trade names
Weighted-Average Amortization Period		6 years 3 months 18 days
Fair Value		$ 5,866
2016 Business Acquisition [Member] | Customer relationships
Weighted-Average Amortization Period		7 years 6 months
Fair Value		$ 39,982
2016 Business Acquisition [Member] | Other purchased intangibles
Weighted-Average Amortization Period		3 years 3 months 18 days
Fair Value		$ 2,997

Goodwill And Intangible Asset61

Goodwill And Intangible Assets (Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets [Abstract]
Amortization of Intangible Assets	$ 129,000	$ 95,300	$ 74,000
Estimated future amortization expense in year 2018	122,294
Estimated future amortization expense in year 2019	103,172
Estimated future amortization expense in year 2020	54,315
Estimated future amortization expense in year 2021	35,280
Estimated future amortization expense in year 2022	30,231
Estimated future amortization expense thereafter	107,648
Finite-Lived Intangible Assets, Net	$ 452,940	$ 478,880

Long Term Debt (Details)

Long Term Debt (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)$ / shares	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Aug. 01, 2017USD ($)	Jun. 10, 2014USD ($)
Debt Instrument [Line Items]
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net	$ (200)	$ (500)	$ 700
Debt Instrument, Face Amount	1,052,500
Debt Instrument, Unamortized Discount	(42,902)	(42,997)
Unamortized Debt Issuance Expense	(7,654)	(7,757)
Debt, Long-term and Short-term, Combined Amount	1,001,944	601,746
Interest Expense	59,200	42,700	43,600
Long-term Debt, Current Maturities	0	0
Total long-term debt, less current portion	1,001,944	601,746
Long-term Debt, Fair Value	1,188,700	792,200
Gain (Loss) on Extinguishment of Debt	(7,962)	0	0
Long-term debt	$ 1,001,944	601,746
6% Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	Jun. 27, 2017
Debt Instrument, Face Amount	$ 650,000	0
Debt Instrument, Interest Rate, Stated Percentage	6.00%
Debt Instrument, Maturity Date	Jul. 15, 2025
Proceeds from Debt, Net of Issuance Costs	$ 636,500
Debt Instrument, Frequency of Periodic Payment	semi-annually
Long-term Debt, Fair Value	$ 684,100
8% Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	0	250,000		$ 250,000
Debt Instrument, Repurchase Amount				$ 265,000
Gain (Loss) on Extinguishment of Debt	8,000
Convertible Debt Securities [Member]
Debt Instrument [Line Items]
Interest Expense, Debt, Excluding Amortization	$ 13,081	13,081	13,081
Debt Instrument, Issuance Date	Jun. 10, 2014
Debt Instrument, Face Amount	$ 402,500	402,500
Debt Instrument, Interest Rate, Stated Percentage	3.25%
Debt Instrument, Maturity Date	Jun. 15, 2029
Proceeds from Debt, Net of Issuance Costs	$ 391,400
Debt Instrument, Unamortized Discount	$ (32,189)	(40,356)			$ (59,000)
Debt Instrument, Convertible, Remaining Discount Amortization Period	3 years 5 months 16 days
Unamortized Debt Issuance Expense	$ (5,667)	(7,002)
Debt Instrument, Frequency of Periodic Payment	semiannually
Debt Instrument, Convertible, Carrying Amount of Equity Component	$ 37,700	37,700			$ 37,700
Interest Expense	22,583	22,005	21,464
Long-term Debt, Fair Value	504,500	516,800
Amortization of Debt Discount (Premium)	8,167	7,707	7,274
Amortization of Debt Issuance Costs	1,335	1,217	$ 1,109
Debt Instrument, Convertible, If-converted Value in Excess of Principal	$ 38,100	75,200
Debt Instrument, Convertible, Conversion Ratio	14.5899
Debt Instrument, Convertible, Conversion Price | $ / shares	$ 68.54
Long-term debt	$ 364,644	$ 355,142

Long Term Debt Long Term Debt (

Long Term Debt Long Term Debt (Schedule Of Maturities Of Long-term Debt) (Details) $ in Thousands	Dec. 31, 2017USD ($)
Long-term Debt, Unclassified [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 0
Long-term Debt, Maturities, Repayments of Principal in Year Two	0
Long-term Debt, Maturities, Repayments of Principal in Year Three	0
Long-term Debt, Maturities, Repayments of Principal in Year Four	402,500
Long-term Debt, Maturities, Repayments of Principal in Year Five	0
Long-term Debt, Maturities, Repayments of Principal after Year Five	650,000
Long-term Debt	$ 1,052,500

Commitments And Contingencies64

Commitments And Contingencies Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Repayments of Lines of Credit	$ 225,000	$ 0	$ 0
Operating Leases, Rent Expense, Net	15,300	10,600	9,000
Operating Leases, Rent Expense, Sublease Rentals	700	600	500
Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals	9,000
Interest Expense	59,200	$ 42,700	$ 43,600
Line of Credit [Member]
Repayments of Lines of Credit	225,000
Line of Credit Facility, Periodic Payment, Interest	$ 500

Commitments And Contingencies65

Commitments And Contingencies Commitments And Contingencies (Summary Of Future Minimum Lease Payments Under Non-Cancelable Operating Leases) (Details) $ in Thousands	Dec. 31, 2017USD ($)
Commitments and Contingencies [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 18,589
Operating Leases, Future Minimum Payments, Due in Two Years	17,325
Operating Leases, Future Minimum Payments, Due in Three Years	13,721
Operating Leases, Future Minimum Payments, Due in Four Years	12,049
Operating Leases, Future Minimum Payments, Due in Five Years	11,199
Operating Leases, Future Minimum Payments, Due Thereafter	13,258
Operating Leases, Future Minimum Payments Due	$ 86,141

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Line Items]
Income tax expense	$ 60,541	$ 59,000	$ 23,283
Deferred Tax Assets, Net of Valuation Allowance	61,575	102,688
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	0	11,900
Deferred Tax Assets, Tax Credit Carryforwards, Research	$ 2,300	$ 3,500
U.S. federal statutory rate	35.00%	35.00%	35.00%
Effective income tax rate	30.30%	27.90%	14.80%
Income before income taxes, domestic operations	$ 61,900	$ 84,800	$ 61,000
Income before income taxes, foreign operations	138,100	126,600	95,900
Liabilities for uncertain income tax positions	45,012	41,218	32,536	$ 34,635
Prepaid tax payments	6,000	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	7,200	5,300	3,400
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	2,100	1,900	1,400
Unrecognized Tax Benefits, Decreases Resulting from Prior Period Tax Positions	(401)	0	(17,107)
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	39,800	37,000	$ 29,800
Unrecognized Tax Benefits, Period Increase (Decrease)	33,300
Tax Cuts and Jobs Act, Incomplete Accounting, Provisional Income Tax Expense (Benefit)	49,200
Tax Cuts and Job Act, Incomplete Accounting, Change in Valuation Allowance	11,900
Foreign Tax Authority [Member]
Income Taxes [Line Items]
Tax Credit Carryforward, Valuation Allowance	0	$ 11,900
California Franchise Tax Board [Member]
Income Taxes [Line Items]
Income Tax Examination, Year under Examination					2,013	2,012
Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	$ 102,200
Operating Loss Carryforwards, Expiration Dates	Dec. 31, 2036
Income Tax Examination, Year under Examination				2,014	2,013	2,012
Massachusetts Department of revenue [Member]
Income Taxes [Line Items]
Income Tax Examination, Year under Examination			2,015	2,014
New York State Division of Taxation and Finance [Member]
Income Taxes [Line Items]
Income Tax Examination, Year under Examination				2,014	2,013	2,012	2,011
Georgia Department of Revenue [Member]
Income Taxes [Line Items]
Income Tax Examination, Year under Examination		2,016	2,015	2,014
Ministry of the Economy, Finance and Industry, France [Member]
Income Taxes [Line Items]
Income Tax Examination, Year under Examination		2,016	2,015	2,014	2,013	2,012	2,011
EVDY [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	$ 89,100
EVDY [Member] | Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Income Tax Examination, Year under Examination				2,014

Income Taxes Income Taxes (Comp

Income Taxes Income Taxes (Components Of Income Tax) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Percent	6.20%	5.50%	6.10%
Current Federal Tax Expense (Benefit)	$ 55,804	$ 46,293	$ 21,745
Current State and Local Tax Expense (Benefit)	3,265	3,874	1,805
Current Foreign Tax Expense (Benefit)	22,904	22,612	16,816
Current Income Tax Expense (Benefit)	81,973	72,779	40,366
Deferred Federal Income Tax Expense (Benefit)	(15,682)	6,822	8,581
Deferred State and Local Income Tax Expense (Benefit)	962	(330)	(3,462)
Deferred Foreign Income Tax Expense (Benefit)	(6,712)	(6,627)	(5,040)
Deferred income taxes	(21,432)	(13,779)	(17,083)
Income tax expense	$ 60,541	$ 59,000	$ 23,283

Income Taxes Income Taxes (Reco

Income Taxes Income Taxes (Reconciliation Of Statutory Federal Income Tax Rate With Effective Income Tax Rate) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
U.S. federal statutory rate	35.00%	35.00%	35.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes	0.80%	1.10%	0.30%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential	(16.10%)	(14.60%)	(15.80%)
Effective Income Tax Rate Reconciliation Subpart F Income	7.20%	9.40%	5.40%
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Percent	(6.20%)	(5.50%)	(6.10%)
Effective Income Tax Rate Reconciliation, Tax Contingencies, Reserve	3.90%	4.70%	(3.30%)
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance	(0.90%)	(1.00%)	1.80%
Effective Income Tax Rate Reconciliation, Deductions, Qualified Production Activities	(1.60%)	(1.10%)	(1.20%)
Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense	$ 0.246	$ 0	$ 0
Tax Cuts and Jobs Act of 2017, Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	$ (0.161)	$ 0	$ 0
Effective Income Tax Rate Reconciliation, Other Adjustments	(0.30%)	(0.10%)	(1.30%)
Effective Income Tax Rate, Continuing Operations	30.30%	27.90%	14.80%

Income Taxes Income Taxes (Defe

Income Taxes Income Taxes (Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Abstract]
Deferred Tax Assets, Operating Loss Carryforwards	$ 29,317	$ 59,806
Deferred Tax Assets, Tax Credit Carryforwards	2,645	16,281
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities	3,165	14,759
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts	1,570	2,624
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	6,476	5,631
Deferred Tax Assets, Property, Plant and Equipment	1,881	2,195
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Impairment Losses	48	74
Deferred Tax Assets, Deferred Income	728	2,361
Deferred Tax Assets, State Taxes	1,777	1,758
Deferred Tax Assets, Other	14,165	9,227
Deferred Tax Assets, Gross	61,772	114,716
Deferred Tax Assets, Valuation Allowance	(197)	(12,028)
Deferred Tax Assets, Net of Valuation Allowance	61,575	102,688
Deferred Tax Liabilities, Intangible Assets	(70,252)	(98,830)
Deferred Tax Liabilities, Prepaid Insurance	(616)	(246)
Deferred Tax Liability, Convertible Debt	(27,504)	(36,592)
Deferred Tax Liabilities, Foreign Other	(1,467)	(2,088)
Deferred Tax Liabilities, Net	(99,839)	(137,756)
Deferred Tax Assets, Net	$ (38,264)	$ (35,068)

Income Taxes Income Taxes (Re70

Income Taxes Income Taxes (Reconciliation Of Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Abstract]
Unrecognized Tax Benefits	$ 45,012	$ 41,218	$ 32,536	$ 34,635
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions	0	2,082	10,361
Unrecognized Tax Benefits, Decreases Resulting from Prior Period Tax Positions	(401)	0	(17,107)
Unrecognized Tax Benefits, Increases Resulting from Current Period Tax Positions	7,223	6,703	8,841
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	(2,639)	0	(4,194)
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations	$ (389)	$ (103)	$ 0

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($)	Feb. 02, 2018	Oct. 31, 2017	Aug. 02, 2017	May 04, 2017	Feb. 09, 2017	Nov. 01, 2016	Aug. 02, 2016	May 05, 2016	Feb. 10, 2016	Dec. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share)										$ 0.01	$ 0.01
Common stock, shares issued										47,854,510	47,443,716
Stock Repurchased										2,100,000
Aggregate cost for repurchase of common stock										$ 58,600,000
Shares surrendered to pay exercise price or satisfy tax withholding obligations for stock options exercised/restricted stock										117,076
Dividend, declaration date		Oct. 31, 2017	Aug. 2, 2017	May 4, 2017	Feb. 9, 2017	Nov. 1, 2016	Aug. 2, 2016	May 5, 2016	Feb. 10, 2016
Dividend amount to be paid, per common share (in dollars per share)		$ 0.3950	$ 0.3850	$ 0.3750	$ 0.3650	$ 0.3550	$ 0.3450	$ 0.3350	$ 0.3250
Dividend, date of record		Nov. 17, 2017	Aug. 14, 2017	May 19, 2017	Feb. 22, 2017	Nov. 18, 2016	Aug. 17, 2016	May 18, 2016	Feb. 23, 2016
Dividend, date to be paid		Dec. 5, 2017	Sep. 1, 2017	Jun. 2, 2017	Mar. 9, 2017	Dec. 5, 2016	Sep. 1, 2016	Jun. 2, 2016	Mar. 10, 2016
Subsequent Event
Class of Stock [Line Items]
Dividend, declaration date	Feb. 2, 2018
Dividend amount to be paid, per common share (in dollars per share)	$ 0.4050
Dividend, date of record	Feb. 22, 2018
Dividend, date to be paid	Mar. 9, 2018
2012 Repurchase Program [Member]
Class of Stock [Line Items]
Maximum number of shares authorized to be repurchased										5,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount										$ 1,938,689
IGC [Member]
Class of Stock [Line Items]
Stock Repurchased											935,231

Stock Options And Employee St72

Stock Options And Employee Stock Purchase Plan (Narrative) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesyrshares	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015USD ($)$ / sharesshares
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense | $	$ 700	$ 1,900	$ 3,700
Estimated forfeiture rate	14.30%	12.71%	14.12%
Share-based compensation expense | $	$ 22,737	$ 13,650	$ 11,793
Number of options granted | shares	0	0	62,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares			$ 15.22
Expiration period of options granted (in years) | yr	10
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value | $	$ 2,100	$ 5,600	$ 10,500
Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Vested In Period, Total Fair Value | $	600	600	700
Exercise of stock options | $	1,108	3,570	4,958
Dividends, Share-based Compensation | $	$ 100	$ 100	$ 100
Number of Shares, Exercisable | shares	361,875	353,258	457,792
Weighted-Average Exercise Price, Exercisable | $ / shares	$ 29.92	$ 26.10	$ 24.78
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years
Stock Options [Member]
Share-based compensation expense | $	$ 400	$ 400	$ 700
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized | $	$ 200
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 4 months 6 days
Restricted Stock And Restricted Stock Unit (RSU) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value | $	$ 15,100	8,000	6,400
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense | $	$ 2,300	$ 3,500	$ 3,800
Shares, Granted | shares	300,330	317,914	252,940
Share-based compensation expense | $	$ 22,200	$ 13,200	$ 11,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized | $	$ 36,600
Restricted (Performance) Stock [Member]
Shares, Granted | shares	85,825	106,780
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares	$ 72.20	$ 44.67
Employee Stock Purchase Plan [Member]
Market value of common stock on the date of grant for incentive stock options	95.00%
Maximum issuance of common stock | shares	2,000,000
Maximum earnings withheld by the employees	15.00%
Number of shares purchased under the plan | shares	3,283	3,918	4,020
Number of shares available for issuance | shares	1,623,243
Restricted Stock [Member]
Shares, Granted | shares	289,230	296,414	234,540
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 years 10 months 21 days
Weighted-Average Grant-Date Fair Value, Granted | $ / shares	$ 61.34	$ 41.27	$ 68.11
Restricted Stock Units (RSUs) [Member]
Shares, Granted | shares	11,100	21,500	18,400
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 years 3 months
2007 Stock Plan [Member]
Maximum issuance of common stock | shares	4,500,000
2015 Stock Option Plan [Member]
Maximum issuance of common stock | shares	4,200,000
Number of shares available for issuance | shares	3,450,474
Minimum [Member] | Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased | $ / shares	$ 70.43
Minimum [Member] | 2007 Stock Plan [Member]
Market value of common stock on the date of grant for incentive stock options	85.00%
Maximum [Member] | Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased | $ / shares	$ 85.73

Stock Options And Employee St73

Stock Options And Employee Stock Purchase Plan (Stock Options) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Outstanding Beginning of Period	413,858	566,428	725,649
Number of options granted	0	0	62,000
Number of Shares, Exercised	(38,183)	(142,870)	(221,221)
Number of Shares, Canceled	0	(9,700)	0
Number of Shares, Outstanding Ending of Period	375,675	413,858	566,428
Number of Shares, Exercisable	361,875	353,258	457,792
Number of Shares, Vested and expected to vest	373,168
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted-Average Exercise Price, Outstanding Beginning of Period	$ 31.09	$ 29.74	$ 24.29
Weighted-Average Exercise Price, Granted	0	0	67.35
Weighted-Average Exercise Price, Exercised	29.03	26.04	22.41
Weighted-Average Exercise Price, Canceled	0	26.92	0
Weighted-Average Exercise Price, Outstanding Ending of Period	31.30	31.09	29.74
Weighted-Average Exercise Price, Exercisable	29.92	$ 26.10	$ 24.78
Weighted-Average Exercise Price, Vested and expected to vest	$ 31.05
Weighted-Average Remaining Contractual Term, Outstanding (in years)	2 years 5 months 16 days
Weighted-Average Remaining Contractual Term, Exercisable (in years)	2 years 3 months 7 days
Weighted-Average Remaining Contractual Term, Vested and expected to vest (in years)	2 years 5 months 5 days
Aggregate Intrinsic Value, Outstanding	$ 16,429,727
Aggregate Intrinsic Value, Exercisable	16,323,743
Aggregate Intrinsic Value, Vested and expected to vest	$ 16,410,477

Stock Options And Employee St74

Stock Options And Employee Stock Purchase Plan (Outstanding And Exercisable Options) (Details)	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	375,675
Options Outstanding, Weighted Average Remaining Contractual Life	2 years 5 months 16 days
Options Outstanding, Weighted Average Exercise Price	$ 31.30
Exercisable Options, Number Exercisable | shares	361,875
Exercisable Options, Weighted Average Exercise Price	$ 29.92
Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	22,000
Options Outstanding, Weighted Average Remaining Contractual Life	1 year 2 months 5 days
Options Outstanding, Weighted Average Exercise Price	$ 17.19
Exercisable Options, Number Exercisable | shares	22,000
Exercisable Options, Weighted Average Exercise Price	$ 17.19
Exercise price range (in dollars per share)	$ 17.19
Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	45,558
Options Outstanding, Weighted Average Remaining Contractual Life	4 months 2 days
Options Outstanding, Weighted Average Exercise Price	$ 20.91
Exercisable Options, Number Exercisable | shares	45,558
Exercisable Options, Weighted Average Exercise Price	$ 20.91
Exercise price range (in dollars per share)	$ 20.91
Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	50,040
Options Outstanding, Weighted Average Remaining Contractual Life	1 year 4 months 6 days
Options Outstanding, Weighted Average Exercise Price	$ 21.67
Exercisable Options, Number Exercisable | shares	50,040
Exercisable Options, Weighted Average Exercise Price	$ 21.67
Exercise price range, min (in dollars per share)	$ 21.67
Range Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	84,092
Options Outstanding, Weighted Average Remaining Contractual Life	2 years 4 months 6 days
Options Outstanding, Weighted Average Exercise Price	$ 22.92
Exercisable Options, Number Exercisable | shares	84,092
Exercisable Options, Weighted Average Exercise Price	$ 22.92
Exercise price range (in dollars per share)	$ 22.92
Range Five [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	14,500
Options Outstanding, Weighted Average Remaining Contractual Life	4 years 7 days
Options Outstanding, Weighted Average Exercise Price	$ 25.13
Exercisable Options, Number Exercisable | shares	14,500
Exercisable Options, Weighted Average Exercise Price	$ 25.13
Exercise price range (in dollars per share)	24.61
Exercise price range, max (in dollars per share)	$ 25.93
Range Six [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	700
Options Outstanding, Weighted Average Remaining Contractual Life	3 years 29 days
Options Outstanding, Weighted Average Exercise Price	$ 27.60
Exercisable Options, Number Exercisable | shares	700
Exercisable Options, Weighted Average Exercise Price	$ 27.60
Exercise price range, min (in dollars per share)	$ 27.60
Range Seven [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	75,585
Options Outstanding, Weighted Average Remaining Contractual Life	3 years 4 months 10 days
Options Outstanding, Weighted Average Exercise Price	$ 29.34
Exercisable Options, Number Exercisable | shares	75,585
Exercisable Options, Weighted Average Exercise Price	$ 29.34
Exercise price range, min (in dollars per share)	$ 29.34
Range Eight [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	13,700
Options Outstanding, Weighted Average Remaining Contractual Life	4 years 2 months 1 day
Options Outstanding, Weighted Average Exercise Price	$ 29.53
Exercisable Options, Number Exercisable | shares	13,700
Exercisable Options, Weighted Average Exercise Price	$ 29.53
Exercise price range, min (in dollars per share)	$ 29.53
Range Nine [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	7,500
Options Outstanding, Weighted Average Remaining Contractual Life	3 years 9 months 26 days
Options Outstanding, Weighted Average Exercise Price	$ 31.07
Exercisable Options, Number Exercisable | shares	7,500
Exercisable Options, Weighted Average Exercise Price	$ 31.07
Exercise price range, min (in dollars per share)	$ 31.07
Range Ten [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number Outstanding | shares	62,000
Options Outstanding, Weighted Average Remaining Contractual Life	3 years 6 months 4 days
Options Outstanding, Weighted Average Exercise Price	$ 67.35
Exercisable Options, Number Exercisable | shares	48,200
Exercisable Options, Weighted Average Exercise Price	$ 67.35
Exercise price range, min (in dollars per share)	$ 67.35

Stock Options And Employee St75

Stock Options And Employee Stock Purchase Plan (Assumptions To Estimate Fair Value Of Stock Options) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Risk-free interest rate	0.00%	0.00%	1.60%
Expected term (in years)	0 days	0 days	5 years 2 months 1 day
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	0.00%	0.00%	0.00%
Weighted average volatility	0.00%	0.00%	0.00%

Stock Options And Employee St76

Stock Options And Employee Stock Purchase Plan (Restricted Stock) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Expected volatility	0.00%	0.00%	0.00%
Risk-free interest rate	0.00%	0.00%	1.60%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 15.22
Restricted (Performance) Stock [Member]
Underlying stock price at valuation date	$ 91.17	$ 63.73
Expected volatility	29.00%	29.80%
Risk-free interest rate	2.17%	1.51%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Shares, Granted	85,825	106,780
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 72.20	$ 44.67
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested, Beginning of Period	705,015	704,804	814,050
Shares, Granted	289,230	296,414	234,540
Shares, Vested	(381,411)	(255,503)	(254,871)
Shares, Canceled	(7,268)	(40,700)	(88,915)
Nonvested, End of Period	605,566	705,015	704,804
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-Average Grant-Date Fair Value, Nonvested, Beginning of Period	$ 41.40	$ 39.08	$ 26.57
Weighted-Average Grant-Date Fair Value, Granted	61.34	41.27	68.11
Weighted-Average Grant-Date Fair Value, Vested	39.71	31.27	25.16
Weighted-Average Grant-Date Fair Value, Canceled	76.08	63.95	40.97
Weighted-Average Grant-Date Fair Value, Nonvested, End of Period	$ 51.57	$ 41.40	$ 39.08
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested, Beginning of Period	51,950	56,245	102,924
Shares, Granted	11,100	21,500	18,400
Shares, Vested	(16,370)	(14,595)	(23,221)
Shares, Canceled	(8,280)	(11,200)	(41,858)
Nonvested, End of Period	38,400	51,950	56,245
Shares, Vested and expected to vest	29,397
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Outstanding, Weighted-Average Remaining Contractual Life (in Years)	1 year 10 months 2 days
Vested and expected to vest, Weighted-Average Remaining Contractual Life (in Years)	1 year 7 months 13 days
Outstanding, Aggregate Intrinsic Value	$ 2,881,152
Vested and expected to vest, Aggregate Intrinsic Value	$ 2,205,686

Defined Contribution 401(k) S77

Defined Contribution 401(k) Savings Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Contribution 401(k) Savings Plan [Abstract]
Defined Contribution Plan, Cost	$ 3	$ 1.8	$ 1.9

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share Reconciliation [Abstract]
Net income	$ 49,871	$ 32,358	$ 31,376	$ 25,820	$ 43,158	$ 45,569	$ 33,770	$ 29,943	$ 139,425	$ 152,439	$ 133,636
Net income available to participating securities									1,792	2,242	2,159
Net earnings available to common shareholders									$ 137,633	$ 150,197	$ 131,477
Basic (in shares)	47,721,700	47,609,819	47,547,118	47,463,231	47,348,372	47,310,011	48,055,783	47,966,718	47,586,242	47,668,357	47,627,853
Dilutive effect of equity incentive plans (in shares)									228,166	201,660	293,911
Dilutive effect of convertible debt (in shares)									854,619	93,209	165,996
Diluted (in shares)	48,437,580	48,521,082	48,948,315	48,766,031	47,862,218	47,494,744	48,265,298	48,238,098	48,669,027	47,963,226	48,087,760
Basic (in dollars per share)	$ 1.03	$ 0.67	$ 0.65	$ 0.54	$ 0.90	$ 0.95	$ 0.69	$ 0.62	$ 2.89	$ 3.15	$ 2.76
Diluted (in dollars per share)	$ 1.02	$ 0.66	$ 0.63	$ 0.52	$ 0.89	$ 0.94	$ 0.69	$ 0.61	$ 2.83	$ 3.13	$ 2.73
Share options excluded from the computation of diluted earnings per share									0

Segment Information - Reportabl

Segment Information - Reportable Segment Information (Reconciliation of Total Segment Operating Income to Consolidated Operating Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total revenues	$ 1,117,838	$ 874,255	$ 720,815
Direct costs by segment	843,783	612,822	480,373
Income from operations	245,708	242,566	199,382
Global operating costs	28,404	19,013	41,257
Cloud Services
Segment Reporting Information [Line Items]
Total revenues	578,956	566,938	504,638
Direct costs by segment	352,912	356,059	294,436
Income from operations	226,044	210,879	210,202
Digital Media
Segment Reporting Information [Line Items]
Total revenues	538,939	307,463	216,374
Direct costs by segment	490,871	256,763	185,937
Income from operations	48,068	50,700	30,437
Elimination of inter-segment revenues
Segment Reporting Information [Line Items]
Total revenues	(57)	(146)	(197)
Reportable segments
Segment Reporting Information [Line Items]
Income from operations	$ 274,112	$ 261,579	$ 240,639

Segment Information - Reporta80

Segment Information - Reportable Segment Information (Total Assets, Capital Expenditures, Depreciation And Amortization) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Other Significant Reconciling Item [Line Items]
Assets	$ 2,453,093	$ 2,062,328
Capital expenditures	39,595	24,746	$ 17,297
Total capital expenditures	39,595	24,746	17,297
Total depreciation and amortization	162,041	122,091	93,213
Cloud Services
Segment Reporting, Other Significant Reconciling Item [Line Items]
Assets	1,078,577	911,327
Capital expenditures	7,031	6,113	7,546
Total depreciation and amortization	68,436	79,533	62,385
Digital Media
Segment Reporting, Other Significant Reconciling Item [Line Items]
Assets	1,317,113	1,124,535
Capital expenditures	32,564	18,633	9,389
Total depreciation and amortization	93,605	42,558	30,008
Reportable segments
Segment Reporting, Other Significant Reconciling Item [Line Items]
Assets	2,395,690	2,035,862
Capital expenditures	39,595	24,746	16,935
Total depreciation and amortization	162,041	122,091	92,393
Corporate
Segment Reporting, Other Significant Reconciling Item [Line Items]
Assets	57,403	26,466
Capital expenditures	0	0	362
Total depreciation and amortization	$ 0	$ 0	$ 820

Segment Information (Details)

Segment Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues	$ 1,117,838	$ 874,255	$ 720,815
Total long-lived assets	532,714	546,483
United States
Revenues	830,800	607,285	492,682
Total long-lived assets	452,143	453,053
Canada
Revenues	78,099	76,775	74,864
Ireland
Revenues	74,430	71,340	43,717
All other countries
Revenues	134,509	118,855	$ 109,552
Total long-lived assets	$ 80,571	$ 93,430

Supplemental Cash Flows Infor82

Supplemental Cash Flows Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Noncash or Part Noncash Divestitures [Line Items]
Interest Paid	$ 35.8	$ 33.1	$ 33.1
Cash paid for income taxes	51.1	37.4	42
Capital Expenditures Incurred but Not yet Paid	0.3	0.4	0.6
Tax Benefit from Stock Options Exercised	2.9	$ 5.4	$ 7.5
Tea Leaves [Member] | Digital Media
Noncash or Part Noncash Divestitures [Line Items]
Noncash or Part Noncash Divestiture, Amount of Consideration Received	$ 57.7

Accumulated Other Comprehensi83

Accumulated Other Comprehensive Income - Accumulated Other Comprehensive Income Roll Forward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance, Unrealized Gains (Losses) on Investments	$ 0	$ 2,449
Beginning Balance, Foreign Currency Translation	(54,649)	(31,573)
Beginning Balance, Total	(54,649)	(29,124)
Other comprehensive income (loss) before reclassifications, Unrealized Gain (Losses) on Investments	0	744
Other comprehensive income (loss) before reclassifications, Foreign Currency Translation	25,559	(23,076)
Other comprehensive income (loss) before reclassifications, Total	25,559	(22,332)
Amounts reclassified from accumulated other comprehensive income, Unrealized Gains (Losses) on Investments	0	(3,193)
Amounts reclassified from accumulated other comprehensive income, Foreign Currency Translation		0
Amounts reclassified from accumulated other comprehensive income, Total	0	(3,193)
Net decrease in other comprehensive income, Unrealized Gains (Losses) on Investments	0	(2,449)	$ (6,939)
Net decrease in other comprehensive income, Foreign Currency Translation	25,559	(23,076)	(15,058)
Net decrease in other comprehensive income, Total	25,559	(25,525)	(21,997)
Ending Balance, Unrealized Gains (Losses) on Investments	0	0	2,449
Ending Balance, Foreign Currency Translation	(29,090)	(54,649)	(31,573)
Ending Balance, Total	$ (29,090)	$ (54,649)	$ (29,124)

Accumulated Other Comprehensi84

Accumulated Other Comprehensive Income (Reclassification out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock [Line Items]
Unrealized gain on available-for-sale investments	$ 0	$ (3,193)
Total reclassifications for the period	0	(3,193)
Other (income) expense, net | Amount Reclassified from Accumulated Other Comprehensive Income
ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock [Line Items]
Unrealized gain on available-for-sale investments	0	(5,149)
Income before income taxes | Amount Reclassified from Accumulated Other Comprehensive Income
ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock [Line Items]
Unrealized gain on available-for-sale investments	0	(5,149)
Income tax expense | Amount Reclassified from Accumulated Other Comprehensive Income
ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock [Line Items]
Unrealized gain on available-for-sale investments	$ 0	$ 1,956

Quarterly Results (Details)

Quarterly Results (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Results [Abstract]
Revenues	$ 316,380	$ 273,616	$ 273,174	$ 254,669	$ 251,837	$ 210,116	$ 211,800	$ 200,502
Gross profit	270,406	231,245	230,015	213,859	211,608	173,124	176,209	166,214	$ 945,525	$ 727,155	$ 597,857
Net income attributable to j2 Global, Inc. common shareholders	$ 49,871	$ 32,358	$ 31,376	$ 25,820	$ 43,158	$ 45,569	$ 33,770	$ 29,943	$ 139,425	$ 152,439	$ 133,636
Net income per common share:
Basic (in dollars per share)	$ 1.03	$ 0.67	$ 0.65	$ 0.54	$ 0.90	$ 0.95	$ 0.69	$ 0.62	$ 2.89	$ 3.15	$ 2.76
Diluted (in dollars per share)	$ 1.02	$ 0.66	$ 0.63	$ 0.52	$ 0.89	$ 0.94	$ 0.69	$ 0.61	$ 2.83	$ 3.13	$ 2.73
Weighted average shares outstanding
Basic (in shares)	47,721,700	47,609,819	47,547,118	47,463,231	47,348,372	47,310,011	48,055,783	47,966,718	47,586,242	47,668,357	47,627,853
Diluted (in shares)	48,437,580	48,521,082	48,948,315	48,766,031	47,862,218	47,494,744	48,265,298	48,238,098	48,669,027	47,963,226	48,087,760

Subsequent Events (Details)

Subsequent Events (Details) - $ / shares	Feb. 02, 2018	Oct. 31, 2017	Aug. 02, 2017	May 04, 2017	Feb. 09, 2017	Nov. 01, 2016	Aug. 02, 2016	May 05, 2016	Feb. 10, 2016
Subsequent Event [Line Items]
Dividends declared date		Oct. 31, 2017	Aug. 2, 2017	May 4, 2017	Feb. 9, 2017	Nov. 1, 2016	Aug. 2, 2016	May 5, 2016	Feb. 10, 2016
Dividend amount to be paid, per common share (in dollars per share)		$ 0.3950	$ 0.3850	$ 0.3750	$ 0.3650	$ 0.3550	$ 0.3450	$ 0.3350	$ 0.3250
Date dividend is payable		Dec. 5, 2017	Sep. 1, 2017	Jun. 2, 2017	Mar. 9, 2017	Dec. 5, 2016	Sep. 1, 2016	Jun. 2, 2016	Mar. 10, 2016
Date shareholders must be on record for dividend		Nov. 17, 2017	Aug. 14, 2017	May 19, 2017	Feb. 22, 2017	Nov. 18, 2016	Aug. 17, 2016	May 18, 2016	Feb. 23, 2016
Subsequent Event
Subsequent Event [Line Items]
Dividends declared date	Feb. 2, 2018
Dividend amount to be paid, per common share (in dollars per share)	$ 0.4050
Date dividend is payable	Mar. 9, 2018
Date shareholders must be on record for dividend	Feb. 22, 2018