Condensed Consolidated Statements Of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Allocated Share-based Compensation Expense	$ 2,770	$ 2,191	$ 8,943	$ 6,538
Revenues:
Total revenues	178,701	153,018	515,992	431,886
Cost of revenues (1)	30,669	28,044	88,350	76,991
Gross profit	148,032	124,974	427,642	354,895
Operating expenses:
Sales and marketing (1)	38,808	37,047	116,819	105,335
Research, development and engineering (1)	8,289	7,637	25,704	22,451
General and administrative (1)	45,202	33,812	138,790	94,209
Total operating expenses	92,299	78,496	281,313	221,995
Income (loss) from operations	55,733	46,478	146,329	132,900
Interest expense (income), net	10,259	10,123	31,453	20,753
Other expense (income), net	1,086	251	390	(254)
Income (loss) before income taxes	44,388	36,104	114,486	112,401
Income Tax Expense (Benefit)	7,013	7,345	16,317	19,828
Net income attributable to j2 Global, Inc. common shareholders	37,375	28,759	98,169	92,573
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 37,375	$ 28,759	$ 98,169	$ 92,573
Net income per common share:
Basic	$ 0.77	$ 0.60	$ 2.03	$ 1.94
Diluted	$ 0.77	$ 0.60	$ 2.02	$ 1.93
Weighted average shares outstanding:
Basic	47,696,224	46,845,477	47,553,075	46,653,836
Diluted	47,953,871	47,163,912	47,777,622	46,988,427
Cash dividends paid per common share	$ 0.3075	$ 0.2775	$ 0.9000	$ 0.8100
Cost of Sales [Member]
Allocated Share-based Compensation Expense	$ 99	$ 82	$ 273	$ 263
Selling and Marketing Expense [Member]
Allocated Share-based Compensation Expense	624	443	1,811	1,360
Research and Development Expense [Member]
Allocated Share-based Compensation Expense	227	175	635	537
General and Administrative Expense [Member]
Allocated Share-based Compensation Expense	$ 1,820	$ 1,491	$ 6,224	$ 4,378