Condensed Consolidated Statements Of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Allocated Share-based Compensation Expense	$ 3,168	$ 1,963	$ 6,173	$ 4,347
Revenues:
Total revenues	176,038	144,744	337,291	278,868
Cost of revenues (1)	29,494	25,558	57,681	48,947
Gross profit	146,544	119,186	279,610	229,921
Operating expenses:
Sales and marketing (1)	40,421	35,329	78,011	68,288
Research, development and engineering (1)	8,969	7,600	17,415	14,814
General and administrative (1)	47,088	31,419	93,588	60,397
Total operating expenses	96,478	74,348	189,014	143,499
Income (loss) from operations	50,066	44,838	90,596	86,422
Interest expense (income), net	10,881	5,682	21,194	10,630
Other expense (income), net	88	(185)	(696)	(505)
Income (loss) before income taxes	39,097	39,341	70,098	76,297
Income Tax Expense (Benefit)	181	4,292	9,304	12,483
Net income attributable to j2 Global, Inc. common shareholders	38,916	35,049	60,794	63,814
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 38,916	$ 35,049	$ 60,794	$ 63,814
Net income per common share:
Basic	$ 0.81	$ 0.73	$ 1.26	$ 1.34
Diluted	$ 0.80	$ 0.73	$ 1.25	$ 1.33
Weighted average shares outstanding:
Basic	47,537,597	46,745,596	47,480,315	46,556,428
Diluted	47,853,574	47,067,767	47,737,006	46,911,574
Cash dividends paid per common share	$ 0.3000	$ 0.2700	$ 0.5925	$ 0.5325
Cost of Sales [Member]
Allocated Share-based Compensation Expense	$ 91	$ 27	$ 174	$ 181
Selling and Marketing Expense [Member]
Allocated Share-based Compensation Expense	603	426	1,187	917
Research and Development Expense [Member]
Allocated Share-based Compensation Expense	213	222	408	362
General and Administrative Expense [Member]
Allocated Share-based Compensation Expense	$ 2,261	$ 1,288	$ 4,404	$ 2,887