Condensed Consolidating Financials Condensed Consolidating Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash and cash equivalents	$ 123,950	$ 255,530	$ 433,663	$ 207,801
Short-term investments	60	79,655
Accounts receivable, net	199,871	114,680
Prepaid expenses and other current assets	24,118	25,722
Deferred income taxes, current	0	7,218
Intercompany receivable	0	0
Total current assets	347,999	482,805
Long-term investments	0	78,563
Property and equipment, net	68,094	57,442
Trade names, net	115,853	118,965
Patent and patent licenses, net	13,928	18,841
Customer relationships, net	208,155	197,319
Goodwill	1,122,810	807,661	635,675
Other purchased intangibles, net	173,755	17,516
Investment in subsidiaries	0	0
Deferred income taxes, non-current	5,289	0
Other assets	6,445	4,607
Total assets	2,062,328	1,783,719
Accounts payable and accrued expenses	178,071	114,384
Income taxes payable	16,753	5,589
Deferred revenue, current	80,384	76,104
Line of credit	178,817	0
Capital lease, current	64	214
Deferred income taxes, current	0	363
Intercompany payable	0	0
Total current liabilities	454,089	196,654
Long-term debt	601,746	592,037
Capital lease, non-current	0	148
Deferred revenue, non-current	1,588	6,538
Liability for uncertain tax positions	46,537	35,917
Deferred income taxes, non-current	40,357	43,989
Other long-term liabilities	3,475	18,228
Total liabilities	1,147,792	893,511
Commitments and contingencies	0	0
Common stock, $0.01 par value	474	479
Additional paid-in capital	308,329	292,064
Retained earnings	660,382	626,789
Accumulated other comprehensive loss	(54,649)	(29,124)	(7,127)
Total stockholders’ equity	914,536	890,208	820,235	706,418
Total liabilities and stockholders’ equity	2,062,328	1,783,719
Consolidating Adjustments
Cash and cash equivalents	0	0		0
Short-term investments	0	0
Accounts receivable, net	(91)	(130)
Prepaid expenses and other current assets	(25,316)	(3,984)
Deferred income taxes, current		(511)
Intercompany receivable	(1,083,028)	(291,127)
Total current assets	(1,108,435)	(295,752)
Long-term investments		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
Investment in subsidiaries	(1,820,494)	(2,147,082)
Deferred income taxes, non-current	(24,895)	0
Other assets	0	(9,149)
Total assets	(2,953,824)	(2,451,983)
Accounts payable and accrued expenses	(25,407)	(130)
Income taxes payable	(66,042)	(3,984)
Deferred revenue, current	0	0
Line of credit	0
Capital lease, current	0	0
Deferred income taxes, current		(511)
Intercompany payable	(1,016,986)	(291,127)
Total current liabilities	(1,108,435)	(295,752)
Long-term debt	0	(9,149)
Capital lease, non-current		0
Deferred revenue, non-current	0	0
Liability for uncertain tax positions	0	0
Deferred income taxes, non-current	(24,895)	0
Other long-term liabilities	0	0
Total liabilities	(1,133,330)	(304,901)
Commitments and contingencies	0	0
Preferred stock, $0.01 par value	0	0
Common stock, $0.01 par value	0	0
Additional paid-in capital	(669,356)	(762,662)
Retained earnings	(1,151,138)	(1,384,420)
Accumulated other comprehensive loss	0	0
Total stockholders’ equity	(1,820,494)	(2,147,082)
Total liabilities and stockholders’ equity	(2,953,824)	(2,451,983)
j2 Global, Inc.
Cash and cash equivalents	23,935	55,516	226,790	0
Short-term investments	0	79,595
Accounts receivable, net	0	0
Prepaid expenses and other current assets	25,922	6,887
Deferred income taxes, current		0
Intercompany receivable	635,740	117,000
Total current assets	685,597	258,998
Long-term investments		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
Investment in subsidiaries	1,091,412	1,051,927
Deferred income taxes, non-current	1,346	0
Other assets	0	8,219
Total assets	1,778,355	1,397,707
Accounts payable and accrued expenses	4,545	4,573
Income taxes payable	0	0
Deferred revenue, current	0	0
Line of credit	178,817
Capital lease, current	0	0
Deferred income taxes, current		511
Intercompany payable	296,658	121,263
Total current liabilities	480,020	126,347
Long-term debt	355,143	354,437
Capital lease, non-current		0
Deferred revenue, non-current	0	0
Liability for uncertain tax positions	0	0
Deferred income taxes, non-current	28,687	24,936
Other long-term liabilities	1,040	1,779
Total liabilities	864,890	507,499
Commitments and contingencies		0
Preferred stock, $0.01 par value	0	0
Common stock, $0.01 par value	474	479
Additional paid-in capital	464,220	292,064
Retained earnings	448,771	595,216
Accumulated other comprehensive loss	0	2,449
Total stockholders’ equity	913,465	890,208
Total liabilities and stockholders’ equity	1,778,355	1,397,707
j2 Cloud Services
Cash and cash equivalents	22,949	9,975	36,810	34,406
Short-term investments	0	0
Accounts receivable, net	11,464	10,679
Prepaid expenses and other current assets	2,266	8,500
Deferred income taxes, current		3,316
Intercompany receivable	281,078	174,127
Total current assets	317,757	206,597
Long-term investments		0
Property and equipment, net	6,318	6,557
Trade names, net	10,097	10,118
Patent and patent licenses, net	601	743
Customer relationships, net	2,519	1,193
Goodwill	58,310	56,296
Other purchased intangibles, net	4,804	4,218
Investment in subsidiaries	730,153	1,095,155
Deferred income taxes, non-current	26,667	14,978
Other assets	443	1,167
Total assets	1,157,669	1,397,022
Accounts payable and accrued expenses	28,179	27,976
Income taxes payable	82,795	9,573
Deferred revenue, current	19,277	19,530
Line of credit	0
Capital lease, current	0
Deferred income taxes, current		0
Intercompany payable	11	0
Total current liabilities	130,262	57,079
Long-term debt	246,604	246,749
Capital lease, non-current		0
Deferred revenue, non-current	1,588	4,667
Liability for uncertain tax positions	41,259	35,917
Deferred income taxes, non-current	0	0
Other long-term liabilities	505	683
Total liabilities	420,218	345,095
Commitments and contingencies	0	0
Preferred stock, $0.01 par value	0	0
Common stock, $0.01 par value	0	0
Additional paid-in capital	89,066	238,631
Retained earnings	648,233	813,058
Accumulated other comprehensive loss	152	238
Total stockholders’ equity	737,451	1,051,927
Total liabilities and stockholders’ equity	1,157,669	1,397,022
Non-guarantor Subsidiaries
Cash and cash equivalents	77,066	190,039	$ 170,063	$ 173,395
Short-term investments	60	60
Accounts receivable, net	188,498	104,131
Prepaid expenses and other current assets	21,246	14,319
Deferred income taxes, current		4,413
Intercompany receivable	166,210	0
Total current assets	453,080	312,962
Long-term investments		0
Property and equipment, net	61,776	50,885
Trade names, net	105,756	108,847
Patent and patent licenses, net	13,327	18,098
Customer relationships, net	205,636	196,126
Goodwill	1,064,500	751,365
Other purchased intangibles, net	168,951	13,298
Investment in subsidiaries	(1,071)	0
Deferred income taxes, non-current	2,171	(14,978)
Other assets	6,002	4,370
Total assets	2,080,128	1,440,973
Accounts payable and accrued expenses	170,754	81,965
Income taxes payable	0	0
Deferred revenue, current	61,107	56,574
Line of credit	0
Capital lease, current	64	214
Deferred income taxes, current		363
Intercompany payable	720,317	169,864
Total current liabilities	952,242	308,980
Long-term debt	(1)	0
Capital lease, non-current		148
Deferred revenue, non-current	0	1,871
Liability for uncertain tax positions	5,278	0
Deferred income taxes, non-current	36,565	19,053
Other long-term liabilities	1,930	15,766
Total liabilities	996,014	345,818
Commitments and contingencies	0	0
Preferred stock, $0.01 par value	0	0
Common stock, $0.01 par value	0	0
Additional paid-in capital	424,399	524,031
Retained earnings	714,516	602,935
Accumulated other comprehensive loss	(54,801)	(31,811)
Total stockholders’ equity	1,084,114	1,095,155
Total liabilities and stockholders’ equity	$ 2,080,128	$ 1,440,973