Income Taxes	3 Months Ended
Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company's tax provision for interim periods is determined using an estimate of the Company's annual effective tax rate. Each quarter the Company updates its estimated annual effective tax rate and, if the estimate changes, makes a cumulative adjustment. j2 Global’s annual effective tax rate is normally lower than the 35% U.S. federal statutory rate and applicable apportioned state tax rates primarily due to anticipated earnings of the Company's subsidiaries outside of the U.S. in jurisdictions where the Company's effective tax rate is lower than in the U.S. The Company's effective tax rate was 30.3% and 29.4% for the three months ended March 31, 2016 and 2015, respectively. j2 Global does not provide for U.S. income taxes on the undistributed earnings of the Company’s foreign operations because the Company intends to permanently reinvest such earnings in foreign jurisdictions and any determination of the amount of unrecognized deferred tax liability related to these earnings is not practicable. Income before income taxes included income from domestic operations of $12.3 million and $11.6 million for the three months ended March 31, 2016 and 2015, respectively, and income from foreign operations of $30.7 million and $19.4 million for the three months ended March 31, 2016 and 2015, respectively. As of March 31, 2016 and December 31, 2015, the Company had $37.7 million and $35.9 million, respectively, in liabilities for uncertain income tax positions. Accrued interest and penalties related to unrecognized tax benefits are recognized in income tax expense on the Company's consolidated statement of income. Cash paid for income taxes net of refunds received was $8.9 million and $8.1 million for the three months ended March 31, 2016 and 2015, respectively. Certain taxes are prepaid during the year and included within prepaid expenses and other current assets on the consolidated balance sheet. The Company's prepaid taxes were $5.5 million and $11.6 million at March 31, 2016 and December 31, 2015, respectively. Income Tax Audits: In November, 2015, the U.S. Internal Revenue Service ("IRS") began its income tax audit of the Company's 2012 and 2013 tax years. During the quarter ended March 31, 2016, the IRS expanded its income tax audit to include the Company's 2014 tax year. j2 Global is under income tax audit by the California Franchise Tax Board (the "FTB") for its 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 for tax years 2011 through 2013. j2 Global was under income tax audit by the New York City Department of Finance ("NYC") for its tax years 2009 through 2011. In February 2016, j2 Global settled its NYC audit for approximately $26,000. 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.

Income Taxes

The Company's tax provision for interim periods is determined using an estimate of the Company's annual effective tax rate. Each quarter the Company updates its estimated annual effective tax rate and, if the estimate changes, makes a cumulative adjustment. j2 Global’s annual effective tax rate is normally lower than the 35% U.S. federal statutory rate and applicable apportioned state tax rates primarily due to anticipated earnings of the Company's subsidiaries outside of the U.S. in jurisdictions where the Company's effective tax rate is lower than in the U.S. The Company's effective tax rate was 30.3% and 29.4% for the three months ended March 31, 2016 and 2015, respectively. j2 Global does not provide for U.S. income taxes on the undistributed earnings of the Company’s foreign operations because the Company intends to permanently reinvest such earnings in foreign jurisdictions and any determination of the amount of unrecognized deferred tax liability related to these earnings is not practicable. Income before income taxes included income from domestic operations of $12.3 million and $11.6 million for the three months ended March 31, 2016 and 2015, respectively, and income from foreign operations of $30.7 million and $19.4 million for the three months ended March 31, 2016 and 2015, respectively.

As of March 31, 2016 and December 31, 2015, the Company had $37.7 million and $35.9 million, respectively, in liabilities for uncertain income tax positions. Accrued interest and penalties related to unrecognized tax benefits are recognized in income tax expense on the Company's consolidated statement of income.

Cash paid for income taxes net of refunds received was $8.9 million and $8.1 million for the three months ended March 31, 2016 and 2015, respectively.

Certain taxes are prepaid during the year and included within prepaid expenses and other current assets on the consolidated balance sheet. The Company's prepaid taxes were $5.5 million and $11.6 million at March 31, 2016 and December 31, 2015, respectively.

Income Tax Audits:

In November, 2015, the U.S. Internal Revenue Service ("IRS") began its income tax audit of the Company's 2012 and 2013 tax years. During the quarter ended March 31, 2016, the IRS expanded its income tax audit to include the Company's 2014 tax year.

j2 Global is under income tax audit by the California Franchise Tax Board (the "FTB") for its 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 for tax years 2011 through 2013.

j2 Global was under income tax audit by the New York City Department of Finance ("NYC") for its tax years 2009 through 2011. In February 2016, j2 Global settled its NYC audit for approximately $26,000.

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.