Condensed Consolidating Financials Condensed Comprehensive Income Statement (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 21,877us-gaap_ProfitLoss	$ 28,765us-gaap_ProfitLoss
Foreign currency translation adjustment, net of tax (benefit)	(15,237)	837
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	380	(2,640)
Other Comprehensive Income (Loss), Net of Tax	(14,857)	(1,803)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	7,020	26,962
Total revenues	161,253us-gaap_Revenues	134,124us-gaap_Revenues
j2 Global, Inc. [Member]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	21,877	0
Foreign currency translation adjustment, net of tax (benefit)	0	0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	311	0
Other Comprehensive Income (Loss), Net of Tax	311	0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	22,188	0
Total revenues	0	0
j2 Cloud Services, Inc. [Member]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	26,251	28,765
Foreign currency translation adjustment, net of tax (benefit)	0	(248)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	69	(2,649)
Other Comprehensive Income (Loss), Net of Tax	69	(2,897)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	26,320	25,868
Total revenues	54,619	51,193
Non-Guarantor Subsidiaries [Member]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	23,539	27,942
Foreign currency translation adjustment, net of tax (benefit)	(15,237)	1,085
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	0	9
Other Comprehensive Income (Loss), Net of Tax	(15,237)	1,094
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	8,302	29,036
Total revenues	116,435	96,634
Consolidation, Eliminations [Member]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(49,790)	(27,942)
Foreign currency translation adjustment, net of tax (benefit)	0	0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	0	0
Other Comprehensive Income (Loss), Net of Tax	0	0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(49,790)	(27,942)
Total revenues	$ (9,801)	$ (13,703)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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