ORGANIZATION AND BASIS OF PRESENTATION - Impact of Topic 606 on Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	$ 46,929		$ 46,929			$ 52,740
Total current assets	276,378		276,378			271,641
Total assets	829,265		829,265			865,164
Other current liabilities	7,912		7,912			9,414
Deferred revenue	12,955		12,955			9,802
Total current liabilities	151,714		151,714			109,561
Other non-current liabilities	7,866		7,866			12,282
Retained earnings	603,343		603,343			626,600
Altisource equity	321,614		321,614			338,612
Total equity	323,141	$ 64,149	323,141	$ 64,149		339,985	$ 62,194
Total liabilities and equity	829,265		829,265			$ 865,164
Revenue	204,575	234,979	620,569	726,147
Cost of revenue	147,580	174,898	457,980	538,244
Gross profit	56,995	60,081	162,589	187,903
Income from operations	20,918	13,459	40,464	41,110
Income (loss) before income taxes and non-controlling interests	16,129	10,357	14,228	32,263
Income tax provision	(6,608)	(2,591)	(6,059)	(7,615)
Net income	9,521	7,766	8,169	24,648
Net income attributable to Altisource	8,667	$ 6,961	6,103	$ 22,541
Balances without adoption of Topic 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	47,718		47,718
Total current assets	277,167		277,167
Total assets	830,054		830,054
Other current liabilities	5,609		5,609
Deferred revenue	8,907		8,907
Total current liabilities	145,363		145,363
Other non-current liabilities	8,552		8,552
Retained earnings	609,797		609,797
Altisource equity	328,068		328,068
Total equity	329,595		329,595
Total liabilities and equity	830,054		830,054
Revenue	200,609		615,812
Cost of revenue	147,972		459,831
Gross profit	52,637		155,981
Income from operations	16,560		33,856
Income (loss) before income taxes and non-controlling interests	11,771		7,620
Income tax provision	(4,444)		(3,245)
Net income	7,327		4,375
Net income attributable to Altisource	6,473		2,309
Accounting Standards Update 2014-09 | Adjustments
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	789		789
Total current assets	789		789
Total assets	789		789
Other current liabilities	(2,303)		(2,303)		$ 300
Deferred revenue	(4,048)		(4,048)		11,200
Total current liabilities	(6,351)		(6,351)
Other non-current liabilities	686		686
Retained earnings	6,454		6,454		$ (10,400)
Altisource equity	6,454		6,454
Total equity	6,454		6,454
Total liabilities and equity	789		789
Revenue	(3,966)		(4,757)
Cost of revenue	392		1,851
Gross profit	(4,358)		(6,608)
Income from operations	(4,358)		(6,608)
Income (loss) before income taxes and non-controlling interests	(4,358)		(6,608)
Income tax provision	2,164		2,814
Net income	(2,194)		(3,794)
Net income attributable to Altisource	$ (2,194)		$ (3,794)