Condensed Consolidating Financials Condensed Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Dec. 31, 2012
Cash and cash equivalents	$ 514,997		$ 207,801	$ 199,181	$ 218,680
Short-term investments	107,418		90,789
Accounts receivable, net of allowances of $3,582 and $4,105, respectively	75,016		67,245
Prepaid expenses and other current assets	24,817		20,064
Deferred income taxes	7,451		3,126
Due from Affiliate, Current	0		0
Total current assets	729,699		389,025
Long-term investments	61,415		47,351
Property and equipment, net	38,787		31,200
Tradenames, net	84,193		83,108
Patent and patent licenses, net	26,892		28,530
Customer Relationships, Net	144,398		100,980
Goodwill	533,403		457,422
Other purchased intangibles, net	8,021		10,915
Investments in and Advances to Affiliates, Amount of Equity	0		0
Other assets	13,196		3,413
Deferred income taxes	0		1,845
Total assets	1,640,004		1,153,789
Accounts payable and accrued expenses	70,781		69,570
Income taxes payable	1,187		1,569
Deferred revenue, current	57,399		36,326
Liability for Uncertain Tax Positions, Current	0		5,535
Deferred Tax Liabilities, Net, Current	591		1,892
Other current liabilities	540		0
Due to Affiliate, Current	0		0
Total current liabilities	130,498		114,892
Long-term Debt	591,464		245,670
Liability for uncertain tax positions	35,793		38,329
Deferred income taxes	61,710		35,833
Deferred revenue, non-current	10,945		11,189
Other long-term liabilities	6,033		1,458
Total liabilities	836,443		447,371
Commitments and contingencies	0		0
Common Stock, Value, Issued	469		461
Additional paid-in capital	270,857		216,872
Retained Earnings (Accumulated Deficit)	535,567		484,850
Accumulated Other Comprehensive Income (Loss), Net of Tax	(3,332)	6,651	4,235
Stockholders' Equity Attributable to Parent	803,561		706,418
Stockholders' Equity Attributable to Noncontrolling Interest			0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	803,561		706,418
Total liabilities and stockholders’ equity	1,640,004		1,153,789
Series A Preferred Stock [Member]
Preferred stock, $0.01 par value	0		0
Series B Preferred Stock [Member]
Preferred stock, $0.01 par value	0		0
j2 Global, Inc. [Member]
Cash and cash equivalents	313,667		0	0	0
Short-term investments	62,647		0
Accounts receivable, net of allowances of $3,582 and $4,105, respectively	0		0
Prepaid expenses and other current assets	1,075		0
Deferred income taxes	0		0
Due from Affiliate, Current	0		0
Total current assets	377,389		0
Long-term investments	54,353		0
Property and equipment, net	0		0
Tradenames, net	0		0
Patent and patent licenses, net	0		0
Customer Relationships, Net	0		0
Goodwill	0		0
Other purchased intangibles, net	0		0
Investments in and Advances to Affiliates, Amount of Equity	231,027		0
Other assets	9,684		0
Deferred income taxes	0		0
Total assets	672,453		0
Accounts payable and accrued expenses	7,486		0
Income taxes payable	0		0
Deferred revenue, current	0		0
Liability for Uncertain Tax Positions, Current			0
Deferred Tax Liabilities, Net, Current	856		0
Other current liabilities	0
Due to Affiliate, Current	42,256		0
Total current liabilities	50,598		0
Long-term Debt	345,409		0
Liability for uncertain tax positions	0		0
Deferred income taxes	24,332		0
Deferred revenue, non-current	0		0
Other long-term liabilities	0		0
Total liabilities	420,339		0
Common Stock, Value, Issued	469		0
Additional paid-in capital	270,857		0
Retained Earnings (Accumulated Deficit)	(19,276)		0
Accumulated Other Comprehensive Income (Loss), Net of Tax	64		0
Stockholders' Equity Attributable to Parent	252,114		0
Stockholders' Equity Attributable to Noncontrolling Interest			0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	252,114		0
Total liabilities and stockholders’ equity	672,453		0
j2 Cloud Services, Inc. [Member]
Cash and cash equivalents	14,799		34,406	50,527	76,712
Short-term investments	39,767		67,848
Accounts receivable, net of allowances of $3,582 and $4,105, respectively	11,213		11,541
Prepaid expenses and other current assets	16,237		16,662
Deferred income taxes	0		0
Due from Affiliate, Current	81,095		4,433
Total current assets	163,111		134,890
Long-term investments	7,061		47,351
Property and equipment, net	8,349		11,232
Tradenames, net	10,273		12,119
Patent and patent licenses, net	921		15,107
Customer Relationships, Net	1,049		6,125
Goodwill	50,803		86,025
Other purchased intangibles, net	4,308		5,306
Investments in and Advances to Affiliates, Amount of Equity	442,726		357,057
Other assets	1,488		1,576
Deferred income taxes	6,309		202
Total assets	696,398		676,990
Accounts payable and accrued expenses	23,100		29,419
Income taxes payable	398		0
Deferred revenue, current	23,312		23,762
Liability for Uncertain Tax Positions, Current			5,532
Deferred Tax Liabilities, Net, Current	1,365		906
Other current liabilities	0
Due to Affiliate, Current	0		0
Total current liabilities	48,175		59,619
Long-term Debt	246,055		245,670
Liability for uncertain tax positions	35,793		38,329
Deferred income taxes	0		0
Deferred revenue, non-current	8,870		10,753
Other long-term liabilities	881		989
Total liabilities	339,774		355,360
Common Stock, Value, Issued	0		461
Additional paid-in capital	231,027		216,871
Retained Earnings (Accumulated Deficit)	120,214		97,754
Accumulated Other Comprehensive Income (Loss), Net of Tax	5,383		6,544
Stockholders' Equity Attributable to Parent	356,624		321,630
Stockholders' Equity Attributable to Noncontrolling Interest			0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	356,624		321,630
Total liabilities and stockholders’ equity	696,398		676,990
Non-Guarantor Subsidiaries [Member]
Cash and cash equivalents	186,531		173,395	148,654	141,968
Short-term investments	5,004		22,941
Accounts receivable, net of allowances of $3,582 and $4,105, respectively	63,803		55,704
Prepaid expenses and other current assets	7,505		3,402
Deferred income taxes	9,081		3,126
Due from Affiliate, Current	0		0
Total current assets	271,924		258,568
Long-term investments	1		0
Property and equipment, net	30,438		19,968
Tradenames, net	73,920		70,989
Patent and patent licenses, net	25,971		13,423
Customer Relationships, Net	143,349		94,855
Goodwill	482,600		371,397
Other purchased intangibles, net	3,713		5,609
Investments in and Advances to Affiliates, Amount of Equity	8,716		0
Other assets	2,024		1,837
Deferred income taxes	3,178		1,643
Total assets	1,045,834		838,289
Accounts payable and accrued expenses	40,195		40,151
Income taxes payable	789		1,569
Deferred revenue, current	34,087		12,564
Liability for Uncertain Tax Positions, Current			3
Deferred Tax Liabilities, Net, Current	0		986
Other current liabilities	540
Due to Affiliate, Current	38,839		4,433
Total current liabilities	114,450		59,706
Long-term Debt	0		0
Liability for uncertain tax positions	0		0
Deferred income taxes	46,865		35,833
Deferred revenue, non-current	2,075		436
Other long-term liabilities	5,152		469
Total liabilities	168,542		96,444
Common Stock, Value, Issued	0		34
Additional paid-in capital	421,401		326,984
Retained Earnings (Accumulated Deficit)	464,670		417,136
Accumulated Other Comprehensive Income (Loss), Net of Tax	(8,779)		(2,309)
Stockholders' Equity Attributable to Parent	877,292		741,845
Stockholders' Equity Attributable to Noncontrolling Interest			0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	877,292		741,845
Total liabilities and stockholders’ equity	1,045,834		838,289
Consolidation, Eliminations [Member]
Cash and cash equivalents	0		0	0	0
Short-term investments	0		0
Accounts receivable, net of allowances of $3,582 and $4,105, respectively	0		0
Prepaid expenses and other current assets	0		0
Deferred income taxes	(1,630)		0
Due from Affiliate, Current	(81,095)		(4,433)
Total current assets	(82,725)		(4,433)
Long-term investments	0		0
Property and equipment, net	0		0
Tradenames, net	0		0
Patent and patent licenses, net	0		0
Customer Relationships, Net	0		0
Goodwill	0		0
Other purchased intangibles, net	0		0
Investments in and Advances to Affiliates, Amount of Equity	(682,469)		(357,057)
Other assets	0		0
Deferred income taxes	(9,487)		0
Total assets	(774,681)		(361,490)
Accounts payable and accrued expenses	0		0
Income taxes payable	0		0
Deferred revenue, current	0		0
Liability for Uncertain Tax Positions, Current			0
Deferred Tax Liabilities, Net, Current	(1,630)		0
Other current liabilities	0
Due to Affiliate, Current	(81,095)		(4,433)
Total current liabilities	(82,725)		(4,433)
Long-term Debt	0		0
Liability for uncertain tax positions	0		0
Deferred income taxes	(9,487)		0
Deferred revenue, non-current	0		0
Other long-term liabilities	0		0
Total liabilities	(92,212)		(4,433)
Common Stock, Value, Issued	0		(34)
Additional paid-in capital	(652,428)		(326,983)
Retained Earnings (Accumulated Deficit)	(30,041)		(30,040)
Accumulated Other Comprehensive Income (Loss), Net of Tax	0		0
Stockholders' Equity Attributable to Parent	(682,469)		(357,057)
Stockholders' Equity Attributable to Noncontrolling Interest			0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(682,469)		(357,057)
Total liabilities and stockholders’ equity	$ (774,681)		$ (361,490)