Basis Of Presentation	6 Months Ended
Jun. 30, 2016
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies [Text Block]	Basis of Presentation j2 Global, Inc., together with its subsidiaries ("j2 Global" or the "Company"), is a leading provider of Internet services. Through its Business Cloud Services Division, the Company provides cloud services to businesses of all sizes, from individuals to enterprises, and licenses its intellectual property ("IP") to third parties. In addition, the Business Cloud Services Division includes our j2 Cloud Connect, which is primarily focused on our number-based voice and fax services. The Digital Media Division specializes in the technology and gaming markets, reaching in-market buyers and influencers in both the consumer and business-to-business space. The accompanying interim condensed 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. The accompanying interim condensed consolidated financial statements are unaudited and have been prepared in accordance with instructions for Form 10-Q and Article 10 of Regulation S-X issued by the Securities and Exchange Commission ("SEC"). Accordingly, they do not include all of the information and note disclosures required by GAAP for complete financial statements although the Company believes that the disclosures made are adequate to make that information not misleading. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been reflected in these interim financial statements. It is suggested that these financial statements be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2015 included in our Annual Report (Form 10-K) filed with the SEC on February 29, 2016. Accordingly, significant accounting policies and other disclosures normally provided have been omitted since such items are disclosed therein. The results of operations for this interim period are not necessarily indicative of the operating results for the full year or for any future period. Use of Estimates The preparation of consolidated financial statements in accordance with accounting principles generally accepted 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 allowances 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 j2 Global reserves for receivables it may not be able to collect. These reserves for the Company's Business 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. 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. Contingent Consideration j2 Global measures 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 5 - 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 the 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 be materially different from the initial estimates or prior quarterly amounts. Changes in the estimated fair value of our contingent earn-out liabilities are reported in operating income, except for the time component of the present value calculation which is reported in interest expense. Segment Reporting Accounting guidance establishes standards for the way that public business enterprises report information about operating segments in annual consolidated financial statements and requires that those enterprises report selected information about operating segments in interim financial reports. Accounting guidance also establishes standards for related disclosures about products and services, geographic areas and major customers. The Company operates as two segments: (1) Business Cloud Services and (2) Digital Media. Reclassifications Certain prior year reported amounts have been reclassified to conform with the 2016 presentation.

Basis of Presentation

j2 Global, Inc., together with its subsidiaries ("j2 Global" or the "Company"), is a leading provider of Internet services. Through its Business Cloud Services Division, the Company provides cloud services to businesses of all sizes, from individuals to enterprises, and licenses its intellectual property ("IP") to third parties. In addition, the Business Cloud Services Division includes our j2 Cloud Connect, which is primarily focused on our number-based voice and fax services. The Digital Media Division specializes in the technology and gaming markets, reaching in-market buyers and influencers in both the consumer and business-to-business space.

The accompanying interim condensed 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.

The accompanying interim condensed consolidated financial statements are unaudited and have been prepared in accordance with instructions for Form 10-Q and Article 10 of Regulation S-X issued by the Securities and Exchange Commission ("SEC"). Accordingly, they do not include all of the information and note disclosures required by GAAP for complete financial statements although the Company believes that the disclosures made are adequate to make that information not misleading. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been reflected in these interim financial statements. It is suggested that these financial statements be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2015 included in our Annual Report (Form 10-K) filed with the SEC on February 29, 2016. Accordingly, significant accounting policies and other disclosures normally provided have been omitted since such items are disclosed therein.

The results of operations for this interim period are not necessarily indicative of the operating results for the full year or for any future period.

Use of Estimates

The preparation of consolidated financial statements in accordance with accounting principles generally accepted 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 allowances 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

j2 Global reserves for receivables it may not be able to collect. These reserves for the Company's Business 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.

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.

Contingent Consideration

j2 Global measures 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 5 - 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 the 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 be materially different from the initial estimates or prior quarterly amounts. Changes in the estimated fair value of our contingent earn-out liabilities are reported in operating income, except for the time component of the present value calculation which is reported in interest expense.

Segment Reporting

Accounting guidance establishes standards for the way that public business enterprises report information about operating segments in annual consolidated financial statements and requires that those enterprises report selected information about operating segments in interim financial reports. Accounting guidance also establishes standards for related disclosures about products and services, geographic areas and major customers. The Company operates as two segments: (1) Business Cloud Services and (2) Digital Media.

Reclassifications

Certain prior year reported amounts have been reclassified to conform with the 2016 presentation.