Condensed Consolidating Financials Condensed Balance Sheet (Details) - Scenario, Unspecified [Domain] - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
ASSETS
Cash and cash equivalents	$ 415,930		$ 433,663	$ 591,881	$ 207,801
Short-term investments	97,188		96,206
Accounts receivable, net of allowances of $4,160 and $3,685, respectively	87,319		91,699
Prepaid expenses and other current assets	27,140		22,602
Deferred income taxes	4,514		2,013
Due from Affiliate, Current	0		0
Total current assets	632,091		646,183
Long-term investments	54,177		60,508
Property and equipment, net	36,778		38,217
Tradenames, net	103,843		105,551
Patent and patent licenses, net	21,857		24,927
Customer Relationships, Net	175,488		163,766
Goodwill	674,084		635,675
Other purchased intangibles, net	14,980		17,556
Investments in and Advances to Affiliates, Amount of Equity	0		0
Other assets	13,511		12,819
Total assets	1,726,809		1,705,202
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	87,081		95,310
Income taxes payable	1,215		0
Deferred revenue, current	75,353		63,457
Capital Lease Obligations, Current	324		258
Deferred Tax Liabilities, Net, Current	362		342
Due to Affiliate, Current	0		0
Total current liabilities	164,335		159,367
Long-term Debt	597,209		593,350
Capital Lease Obligations, Noncurrent	195		141
Liability for uncertain tax positions	25,136		37,551
Deferred income taxes	63,267		61,960
Deferred revenue, non-current	8,222		10,182
Other long-term liabilities	19,242		22,416
Total liabilities	$ 877,606		$ 884,967
Commitments and contingencies
Common Stock, Value, Issued	$ 476		$ 474
Additional paid-in capital	282,702		273,304
Retained Earnings (Accumulated Deficit)	584,831		553,584
Accumulated Other Comprehensive Income (Loss), Net of Tax	(18,806)	$ (21,984)	(7,127)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	849,203		820,235
Total liabilities and stockholders’ equity	1,726,809		1,705,202
Series A Preferred Stock [Member]
LIABILITIES AND STOCKHOLDERS' EQUITY
Preferred stock, $0.01 par value	0		0
Series B Preferred Stock [Member]
LIABILITIES AND STOCKHOLDERS' EQUITY
Preferred stock, $0.01 par value	0		0
j2 Global, Inc. [Member]
ASSETS
Cash and cash equivalents	220,787		226,790	391,483	0
Short-term investments	55,489		47,880
Accounts receivable, net of allowances of $4,160 and $3,685, respectively	0		0
Prepaid expenses and other current assets	1,595		776
Deferred income taxes	782		1,271
Due from Affiliate, Current	72,000		110,000
Total current assets	350,653		386,717
Long-term investments	47,119		55,452
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	889,340		826,289
Other assets	8,786		9,328
Total assets	1,295,898		1,277,786
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	4,500		2,834
Income taxes payable	0		0
Deferred revenue, current	0		0
Capital Lease Obligations, Current	0		0
Deferred Tax Liabilities, Net, Current	0		0
Due to Affiliate, Current	54,901		76,366
Total current liabilities	59,401		79,200
Long-term Debt	350,747		347,163
Capital Lease Obligations, Noncurrent	0		0
Liability for uncertain tax positions	0		0
Deferred income taxes	26,759		21,728
Deferred revenue, non-current	0		0
Other long-term liabilities	1,071		744
Total liabilities	437,978		448,835
Common Stock, Value, Issued	476		474
Additional paid-in capital	282,702		273,304
Retained Earnings (Accumulated Deficit)	574,683		555,158
Accumulated Other Comprehensive Income (Loss), Net of Tax	59		15
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	857,920		828,951
Total liabilities and stockholders’ equity	1,295,898		1,277,786
j2 Cloud Services, Inc. [Member]
ASSETS
Cash and cash equivalents	11,400		36,810	29,968	34,406
Short-term investments	41,637		48,261
Accounts receivable, net of allowances of $4,160 and $3,685, respectively	12,423		11,167
Prepaid expenses and other current assets	16,989		12,689
Deferred income taxes	0		0
Due from Affiliate, Current	105,827		74,938
Total current assets	188,276		183,865
Long-term investments	7,058		5,056
Property and equipment, net	7,088		8,011
Tradenames, net	10,172		10,231
Patent and patent licenses, net	815		886
Customer Relationships, Net	1,699		2,206
Goodwill	54,087		52,131
Other purchased intangibles, net	4,248		4,276
Investments in and Advances to Affiliates, Amount of Equity	943,491		900,681
Other assets	2,718		1,368
Total assets	1,219,652		1,168,711
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	28,429		28,414
Income taxes payable	2,770		0
Deferred revenue, current	20,461		23,091
Capital Lease Obligations, Current	0		0
Deferred Tax Liabilities, Net, Current	0		0
Due to Affiliate, Current	0		0
Total current liabilities	51,660		51,505
Long-term Debt	246,462		246,187
Capital Lease Obligations, Noncurrent	0		0
Liability for uncertain tax positions	25,136		37,551
Deferred income taxes	0		(1,837)
Deferred revenue, non-current	6,227		8,187
Other long-term liabilities	827		829
Total liabilities	330,312		342,422
Common Stock, Value, Issued	0		0
Additional paid-in capital	235,332		232,340
Retained Earnings (Accumulated Deficit)	648,467		584,591
Accumulated Other Comprehensive Income (Loss), Net of Tax	5,541		9,358
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	889,340		826,289
Total liabilities and stockholders’ equity	1,219,652		1,168,711
Non-Guarantor Subsidiaries [Member]
ASSETS
Cash and cash equivalents	183,743		170,063	170,430	173,395
Short-term investments	62		65
Accounts receivable, net of allowances of $4,160 and $3,685, respectively	74,939		80,532
Prepaid expenses and other current assets	10,111		9,137
Deferred income taxes	3,732		742
Due from Affiliate, Current	0		1,428
Total current assets	272,587		261,967
Long-term investments	0		0
Property and equipment, net	29,690		30,206
Tradenames, net	93,671		95,320
Patent and patent licenses, net	21,042		24,041
Customer Relationships, Net	173,789		161,560
Goodwill	619,997		583,544
Other purchased intangibles, net	10,732		13,280
Investments in and Advances to Affiliates, Amount of Equity	8,717		8,716
Other assets	2,007		2,123
Total assets	1,232,232		1,180,757
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	54,195		64,062
Income taxes payable	0		0
Deferred revenue, current	54,892		40,366
Capital Lease Obligations, Current	324		258
Deferred Tax Liabilities, Net, Current	362		342
Due to Affiliate, Current	122,926		110,000
Total current liabilities	232,699		215,028
Long-term Debt	0		0
Capital Lease Obligations, Noncurrent	195		141
Liability for uncertain tax positions	0		0
Deferred income taxes	36,508		42,069
Deferred revenue, non-current	1,995		1,995
Other long-term liabilities	17,344		20,843
Total liabilities	288,741		280,076
Common Stock, Value, Issued	0		0
Additional paid-in capital	422,108		421,676
Retained Earnings (Accumulated Deficit)	545,789		495,505
Accumulated Other Comprehensive Income (Loss), Net of Tax	(24,406)		(16,500)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	943,491		900,681
Total liabilities and stockholders’ equity	1,232,232		1,180,757
Consolidation, Eliminations [Member]
ASSETS
Cash and cash equivalents	0		0	$ 0	$ 0
Short-term investments	0		0
Accounts receivable, net of allowances of $4,160 and $3,685, respectively	(43)		0
Prepaid expenses and other current assets	(1,555)		0
Deferred income taxes	0		0
Due from Affiliate, Current	(177,827)		(186,366)
Total current assets	(179,425)		(186,366)
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	(1,841,548)		(1,735,686)
Other assets	0		0
Total assets	(2,020,973)		(1,922,052)
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	(43)		0
Income taxes payable	(1,555)		0
Deferred revenue, current	0		0
Capital Lease Obligations, Current	0		0
Deferred Tax Liabilities, Net, Current	0		0
Due to Affiliate, Current	(177,827)		(186,366)
Total current liabilities	(179,425)		(186,366)
Long-term Debt	0		0
Capital Lease Obligations, Noncurrent	0		0
Liability for uncertain tax positions	0		0
Deferred income taxes	0		0
Deferred revenue, non-current	0		0
Other long-term liabilities	0		0
Total liabilities	(179,425)		(186,366)
Common Stock, Value, Issued	0		0
Additional paid-in capital	(657,440)		(654,016)
Retained Earnings (Accumulated Deficit)	(1,184,108)		(1,081,670)
Accumulated Other Comprehensive Income (Loss), Net of Tax	0		0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(1,841,548)		(1,735,686)
Total liabilities and stockholders’ equity	$ (2,020,973)		$ (1,922,052)