Condensed Consolidating Financials Condensed Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
ASSETS
Cash and cash equivalents	$ 285,563		$ 255,530	$ 272,368	$ 433,663
Short-term investments	39,908		79,655
Accounts receivable, net of allowances of $6,643 and $4,261, respectively	114,581		114,680
Prepaid expenses and other current assets	26,567		25,722
Deferred income taxes	0		7,218
Due from Affiliate, Current	0		0
Total current assets	466,619		482,805
Long-term investments	53,421		78,563
Property and equipment, net	61,437		57,442
Trade names, net	118,891		118,965
Patent and patent licenses, net	14,441		18,841
Customer Relationships, Net	175,434		197,319
Goodwill	853,791		807,661
Other purchased intangibles, net	16,888		17,516
Investments in and Advances to Affiliates, Amount of Equity	0		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	4,454		0
Other assets	3,769		4,607
Total assets	1,769,145		1,783,719
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	101,830		114,384
Income taxes payable	2,207		5,589
Deferred revenue, current	76,259		76,104
Capital Lease Obligations, Current	191		214
Deferred Tax Liabilities, Net, Current	0		363
Due to Affiliate, Current	0		0
Total current liabilities	180,487		196,654
Long-term Debt	599,260		592,037
Capital Lease Obligations, Noncurrent	12		148
Liability for uncertain tax positions	44,418		35,917
Deferred income taxes	39,975		43,989
Deferred revenue, non-current	2,354		6,538
Other long-term liabilities	4,445		18,228
Total liabilities	870,951		893,511
Commitments and contingencies	0		0
Common Stock, Value, Issued	472		479
Additional paid-in capital	304,385		292,064
Retained Earnings (Accumulated Deficit)	634,386		626,789
Accumulated Other Comprehensive Income (Loss), Net of Tax	(41,049)	$ (38,472)	(29,124)
Stockholders' Equity Attributable to Parent	898,194		890,208
Total liabilities and stockholders' equity	1,769,145		1,783,719
Series A Preferred Stock [Member]
LIABILITIES AND STOCKHOLDERS' EQUITY
Preferred stock, $0.01 par value	0		0
j2 Global, Inc. [Member]
ASSETS
Cash and cash equivalents	46,203		55,516	109,554	226,790
Short-term investments	39,845		79,595
Accounts receivable, net of allowances of $6,643 and $4,261, respectively	0		0
Prepaid expenses and other current assets	32,347		6,887
Deferred income taxes			0
Due from Affiliate, Current	130,000		117,000
Total current assets	248,395		258,998
Long-term investments	53,421		78,563
Property and equipment, net	0		0
Trade names, 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	1,062,379		1,051,927
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	0		0
Other assets	0		8,219
Total assets	1,364,195		1,397,707
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	6,461		4,573
Income taxes payable	0		0
Deferred revenue, current	0		0
Capital Lease Obligations, Current	0		0
Deferred Tax Liabilities, Net, Current			511
Due to Affiliate, Current	77,121		121,263
Total current liabilities	83,582		126,347
Long-term Debt	352,858		354,437
Capital Lease Obligations, Noncurrent	0		0
Liability for uncertain tax positions	0		0
Deferred income taxes	29,111		24,936
Deferred revenue, non-current	0		0
Other long-term liabilities	1,522		1,779
Total liabilities	467,073		507,499
Commitments and contingencies	0		0
Preferred stock, $0.01 par value	0		0
Common Stock, Value, Issued	472		479
Additional paid-in capital	460,276		292,064
Retained Earnings (Accumulated Deficit)	436,285		595,216
Accumulated Other Comprehensive Income (Loss), Net of Tax	89		2,449
Stockholders' Equity Attributable to Parent	897,122		890,208
Total liabilities and stockholders' equity	1,364,195		1,397,707
j2 Cloud Services, LLC [Member]
ASSETS
Cash and cash equivalents	8,433		9,975	11,854	36,810
Short-term investments	0		0
Accounts receivable, net of allowances of $6,643 and $4,261, respectively	13,872		10,679
Prepaid expenses and other current assets	1,846		8,500
Deferred income taxes			3,316
Due from Affiliate, Current	201,099		174,127
Total current assets	225,250		206,597
Long-term investments	0		0
Property and equipment, net	6,763		6,557
Trade names, net	10,130		10,118
Patent and patent licenses, net	637		743
Customer Relationships, Net	2,543		1,193
Goodwill	61,419		56,296
Other purchased intangibles, net	4,438		4,218
Investments in and Advances to Affiliates, Amount of Equity	723,601		1,095,155
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	22,475		14,978
Other assets	457		1,167
Total assets	1,057,713		1,397,022
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	24,111		27,976
Income taxes payable	7,138		9,573
Deferred revenue, current	19,977		19,530
Capital Lease Obligations, Current	0		0
Deferred Tax Liabilities, Net, Current			0
Due to Affiliate, Current	0		0
Total current liabilities	51,226		57,079
Long-term Debt	246,402		246,749
Capital Lease Obligations, Noncurrent	0		0
Liability for uncertain tax positions	44,418		35,917
Deferred income taxes	0		0
Deferred revenue, non-current	2,354		4,667
Other long-term liabilities	581		683
Total liabilities	344,981		345,095
Commitments and contingencies	0		0
Preferred stock, $0.01 par value	0		0
Common Stock, Value, Issued	0		0
Additional paid-in capital	89,066		238,631
Retained Earnings (Accumulated Deficit)	623,518		813,058
Accumulated Other Comprehensive Income (Loss), Net of Tax	148		238
Stockholders' Equity Attributable to Parent	712,732		1,051,927
Total liabilities and stockholders' equity	1,057,713		1,397,022
Non-Guarantor Subsidiaries [Member]
ASSETS
Cash and cash equivalents	230,927		190,039	150,960	170,063
Short-term investments	63		60
Accounts receivable, net of allowances of $6,643 and $4,261, respectively	100,714		104,131
Prepaid expenses and other current assets	17,015		14,319
Deferred income taxes			4,413
Due from Affiliate, Current	0		0
Total current assets	348,719		312,962
Long-term investments	0		0
Property and equipment, net	54,674		50,885
Trade names, net	108,761		108,847
Patent and patent licenses, net	13,804		18,098
Customer Relationships, Net	172,891		196,126
Goodwill	792,372		751,365
Other purchased intangibles, net	12,450		13,298
Investments in and Advances to Affiliates, Amount of Equity	(1,072)		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	2,284		(14,978)
Other assets	3,312		4,370
Total assets	1,508,195		1,440,973
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	90,973		81,965
Income taxes payable	0		0
Deferred revenue, current	56,282		56,574
Capital Lease Obligations, Current	191		214
Deferred Tax Liabilities, Net, Current			363
Due to Affiliate, Current	253,978		169,864
Total current liabilities	401,424		308,980
Long-term Debt	0		0
Capital Lease Obligations, Noncurrent	12		148
Liability for uncertain tax positions	0		0
Deferred income taxes	31,169		19,053
Deferred revenue, non-current	0		1,871
Other long-term liabilities	2,342		15,766
Total liabilities	434,947		345,818
Commitments and contingencies	0		0
Preferred stock, $0.01 par value	0		0
Common Stock, Value, Issued	0		0
Additional paid-in capital	425,550		524,031
Retained Earnings (Accumulated Deficit)	688,984		602,935
Accumulated Other Comprehensive Income (Loss), Net of Tax	(41,286)		(31,811)
Stockholders' Equity Attributable to Parent	1,073,248		1,095,155
Total liabilities and stockholders' equity	1,508,195		1,440,973
Consolidation, Eliminations [Member]
ASSETS
Cash and cash equivalents	0		0	$ 0	$ 0
Short-term investments	0		0
Accounts receivable, net of allowances of $6,643 and $4,261, respectively	(5)		(130)
Prepaid expenses and other current assets	(24,641)		(3,984)
Deferred income taxes			(511)
Due from Affiliate, Current	(331,099)		(291,127)
Total current assets	(355,745)		(295,752)
Long-term investments	0		0
Property and equipment, net	0		0
Trade names, 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	(1,784,908)		(2,147,082)
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	(20,305)		0
Other assets	0		(9,149)
Total assets	(2,160,958)		(2,451,983)
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	(19,715)		(130)
Income taxes payable	(4,931)		(3,984)
Deferred revenue, current	0		0
Capital Lease Obligations, Current	0		0
Deferred Tax Liabilities, Net, Current			(511)
Due to Affiliate, Current	(331,099)		(291,127)
Total current liabilities	(355,745)		(295,752)
Long-term Debt	0		(9,149)
Capital Lease Obligations, Noncurrent	0		0
Liability for uncertain tax positions	0		0
Deferred income taxes	(20,305)		0
Deferred revenue, non-current	0		0
Other long-term liabilities	0		0
Total liabilities	(376,050)		(304,901)
Commitments and contingencies	0		0
Preferred stock, $0.01 par value	0		0
Common Stock, Value, Issued	0		0
Additional paid-in capital	(670,507)		(762,662)
Retained Earnings (Accumulated Deficit)	(1,114,401)		(1,384,420)
Accumulated Other Comprehensive Income (Loss), Net of Tax	0		0
Stockholders' Equity Attributable to Parent	(1,784,908)		(2,147,082)
Total liabilities and stockholders' equity	$ (2,160,958)		$ (2,451,983)