Restatement of Previously Issued Consolidated Financial Statements Restated Statements of Income (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net revenues		$ 91,015	$ 119,936	$ 296,102	$ 319,283
Cost of revenues	[1]	45,576	49,138	139,386	143,469
Research and development		20,926	31,030	67,234	84,904
Selling, general and administrative		34,881	28,827	103,049	84,621
Fair value adjustment to contingent consideration obligation included in net income		0	(1,349)	0	1,766
Charges		2,312	924	11,715	4,973
Depreciation and amortization		23,459	23,592	71,098	70,467
Total costs and expenses		127,154	132,162	392,482	390,200
Loss from continuing operations		(36,139)	(12,226)	(96,380)	(70,917)
Interest income		3,274	271	9,157	1,492
Interest expense		(25,555)	(1,596)	(48,016)	(5,006)
Other expense, net		(256)	(151)	2,374	136
Loss from continuing operations, before taxes		(58,031)	(13,702)	(131,239)	(74,295)
Benefit for income taxes		12,825	3,610	17,973	18,760
Net loss from continuing operations		(45,206)	(10,092)	(113,266)	(55,535)
Net income from discontinued operations, net of tax	[2]	8,842	9,307	(14,067)	27,106
Net loss		(36,364)	(785)	(127,333)	(28,429)
Net loss attributable to redeemable noncontrolling interests		(1,276)	(3,347)	(6,980)	(9,494)
Net loss attributable to Synchronoss		$ (35,088)	$ 2,562	$ (120,353)	$ (18,935)
Basic:
Continuing operations (usd per share)		$ (0.98)	$ (0.15)	$ (2.38)	$ (1.06)
Discontinued operations (usd per share)	[2]	0.20	0.21	(0.32)	0.62
Basic (usd per share)		(0.78)	0.06	(2.70)	(0.44)
Diluted:
Continuing operations (usd per share)		(0.98)	(0.15)	(2.38)	(1.06)
Discontinued operations (usd per share)	[2]	0.20	0.21	(0.32)	0.62
Diluted (usd per share)		$ (0.78)	$ 0.06	$ (2.70)	$ (0.44)
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Basic (in shares)		44,893	43,560	44,576	43,469
Diluted (in shares)		44,893	43,560	44,576	43,469
As Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net revenues			$ 132,480		$ 354,954
Cost of revenues			49,073		143,988
Research and development			28,141		78,408
Selling, general and administrative			30,934		87,809
Fair value adjustment to contingent consideration obligation included in net income			572		7,299
Charges			924		4,973
Depreciation and amortization			24,692		74,009
Total costs and expenses			134,336		396,486
Loss from continuing operations			(1,856)		(41,532)
Interest income			271		1,492
Interest expense			(1,596)		(5,006)
Other expense, net			(167)		(186)
Loss from continuing operations, before taxes			(3,348)		(45,232)
Benefit for income taxes			(1,621)		814
Net loss from continuing operations			(4,969)		(44,418)
Net income from discontinued operations, net of tax			9,802		30,865
Net loss			4,833		(13,553)
Net loss attributable to redeemable noncontrolling interests			(2,843)		(8,836)
Net loss attributable to Synchronoss			$ 7,676		$ (4,717)
Basic:
Continuing operations (usd per share)			$ (0.05)		$ (0.82)
Discontinued operations (usd per share)			0.23		0.71
Basic (usd per share)			0.18		(0.11)
Diluted:
Continuing operations (usd per share)			(0.05)		(0.82)
Discontinued operations (usd per share)			0.23		0.71
Diluted (usd per share)			$ 0.18		$ (0.11)
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Basic (in shares)			43,560		43,488
Diluted (in shares)			43,560		43,488
Revenue - Hosting | Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net revenues			$ (6,440)		$ (17,161)
Selling, general and administrative			2		155
Total costs and expenses			2		155
Loss from continuing operations			(6,442)		(17,316)
Loss from continuing operations, before taxes			(6,442)		(17,316)
Net loss from continuing operations			(6,442)		(17,316)
Net loss			(6,442)		(17,316)
Net loss attributable to Synchronoss			(6,442)		(17,316)
Revenue - Evidence of Arrangement and Other Revenue | Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net revenues			(7,648)		(9,523)
Selling, general and administrative			(2,246)		(2,718)
Total costs and expenses			(2,246)		(2,718)
Loss from continuing operations			(5,402)		(6,805)
Other expense, net			16		322
Loss from continuing operations, before taxes			(5,386)		(6,483)
Net loss from continuing operations			(5,386)		(6,483)
Net income from discontinued operations, net of tax			(2,427)		(5,726)
Net loss			(7,813)		(12,209)
Net loss attributable to Synchronoss			(7,813)		(12,209)
Acquisitions & Divestiture | Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net revenues			1,544		(8,987)
Cost of revenues			65		(107)
Selling, general and administrative			156		536
Fair value adjustment to contingent consideration obligation included in net income			(1,921)		(5,533)
Depreciation and amortization			(1,111)		(3,333)
Total costs and expenses			(2,811)		(8,437)
Loss from continuing operations			4,355		(550)
Loss from continuing operations, before taxes			4,355		(550)
Net loss from continuing operations			4,355		(550)
Net income from discontinued operations, net of tax			(272)		(272)
Net loss			4,083		(822)
Net loss attributable to Synchronoss			4,083		(822)
Capitalized Software and Other | Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Cost of revenues					(412)
Research and development			2,889		6,496
Selling, general and administrative			(19)		(1,161)
Depreciation and amortization			11		(209)
Total costs and expenses			2,881		4,714
Loss from continuing operations			(2,881)		(4,714)
Loss from continuing operations, before taxes			(2,881)		(4,714)
Benefit for income taxes			0
Net loss from continuing operations			(2,881)		(4,714)
Net income from discontinued operations, net of tax			(1)
Net loss			(2,882)		(4,714)
Net loss attributable to redeemable noncontrolling interests			(504)		(658)
Net loss attributable to Synchronoss			(2,378)		(4,056)
Income Taxes | Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Benefit for income taxes			5,231		17,946
Net loss from continuing operations			5,231		17,946
Net income from discontinued operations, net of tax			2,205		2,239
Net loss			7,436		20,185
Net loss attributable to Synchronoss			$ 7,436		$ 20,185

[1] Cost of revenues excludes depreciation and amortization which is shown separately.

[2] See Note 4 - Acquisitions and Divestitures for transactions classified as discontinued operations.