Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common stock	Preferred stock	Additional paid-in capital	Accumulated deficit	Accumulated other comprehensive loss	Treasury stock	Parent	Noncontrolling interest	Series A Preferred Stock	Series A Preferred Stock Preferred stock	Series A-1 Preferred Stock [Member]	Series A-1 Preferred Stock [Member] Preferred stock	Preferred Class A [Member] Preferred stock	Series B Preferred Stock	Series B Preferred Stock Preferred stock
Common stock, beginning balance (in shares) at Dec. 31, 2017		30,632,000					3,135,000
Preferred stock, beginning balance (in shares) at Dec. 31, 2017											127,000		0			555,000
Increase (Decrease) in Stockholders' Equity
Shares converted (in shares)											0		0	0		0
Common stock issued upon vesting of restricted stock (in shares)		221,000
Stock Issued During Period, Shares, Purchase of Assets		100,000
Exercise of stock warrants (in shares)		1,250,000
Common stock sold through ATM offering (in shares)		0
Common stock repurchased through business combination (in shares)							0
Tax withholding upon vesting of restricted stock (in shares)							61,000
Preferred stock, ending balance (in shares) at Jun. 30, 2018											127,000		0			555,000
Common stock, ending balance (in shares) at Jun. 30, 2018		32,203,000					3,196,000
Beginning balance at Dec. 31, 2017				$ 494,732	$ (254,692)	$ (599)	$ (63,816)		$ (3,505)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Stock-based compensation to employees and directors				5,368					4,040
Issuance and exercise of stock warrants				50,587
Proceeds from sale of common stock, net of offering costs	$ 0			0
Other				(505)	0				505
Cumulative effect of change in accounting principle					5,040
Net loss attributable to stockholders of Overstock.com, Inc.	(115,820)				(115,820)
Net other comprehensive income	8					8
Common stock repurchased through business combination							0
Tax withholding upon vesting of restricted stock							(2,846)		(1,680)
Proceeds from security token offering, net	95,900								78,442
Net loss attributable to noncontrolling interests	(4,552)								(4,552)
Fair value of noncontrolling interest at acquisition									4,468
Ending balance at Jun. 30, 2018	198,108	$ 3	$ 0	553,112	(365,472)	(591)	$ (66,662)	$ 120,390	77,718
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Common stock issued for asset purchase				2,930
Common stock, beginning balance (in shares) at Mar. 31, 2018		32,048,000					3,182,000
Preferred stock, beginning balance (in shares) at Mar. 31, 2018											127,000		0			555,000
Increase (Decrease) in Stockholders' Equity
Shares converted (in shares)											0		0	0		0
Common stock issued upon vesting of restricted stock (in shares)		55,000
Stock Issued During Period, Shares, Purchase of Assets		100,000
Exercise of stock warrants (in shares)		0
Common stock sold through ATM offering (in shares)		0
Common stock repurchased through business combination (in shares)							0
Tax withholding upon vesting of restricted stock (in shares)							14,000
Preferred stock, ending balance (in shares) at Jun. 30, 2018											127,000		0			555,000
Common stock, ending balance (in shares) at Jun. 30, 2018		32,203,000					3,196,000
Beginning balance at Mar. 31, 2018				547,184	(300,561)	(595)	$ (66,170)		76,232
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Stock-based compensation to employees and directors				2,973					0
Issuance and exercise of stock warrants				25
Proceeds from sale of common stock, net of offering costs				0
Other				0	0				0
Cumulative effect of change in accounting principle					0
Net loss attributable to stockholders of Overstock.com, Inc.	(64,911)				(64,911)
Net other comprehensive income	4					4
Common stock repurchased through business combination							0
Tax withholding upon vesting of restricted stock							(492)		0
Proceeds from security token offering, net									2,491
Net loss attributable to noncontrolling interests	(1,005)								(1,005)
Fair value of noncontrolling interest at acquisition									0
Ending balance at Jun. 30, 2018	$ 198,108	$ 3	0	553,112	(365,472)	(591)	$ (66,662)	120,390	77,718
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Common stock issued for asset purchase				2,930
Common Stock, Shares, Outstanding		29,007,000
Common Stock, Shares, Outstanding	32,146,000
Common stock, beginning balance (in shares) at Dec. 31, 2018		35,346,000					3,200,000
Preferred stock, beginning balance (in shares) at Dec. 31, 2018										127,000	127,000	0	0		355,000	355,000
Increase (Decrease) in Stockholders' Equity
Shares converted (in shares)											123,000		(123,000)	1,000		(1,000)
Common stock issued upon vesting of restricted stock (in shares)		255,000
Stock Issued During Period, Shares, Purchase of Assets		0
Exercise of stock warrants (in shares)		0
Common stock sold through ATM offering (in shares)		2,960,000
Common stock repurchased through business combination (in shares)							47,000
Tax withholding upon vesting of restricted stock (in shares)							75,000
Preferred stock, ending balance (in shares) at Jun. 30, 2019										3,000	3,000	123,000	123,000		356,000	356,000
Common stock, ending balance (in shares) at Jun. 30, 2019		38,561,000					3,322,000
Beginning balance at Dec. 31, 2018	$ 210,706			657,981	(458,897)	(584)	$ (66,757)		78,960
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Stock-based compensation to employees and directors				9,156					0
Issuance and exercise of stock warrants				0
Proceeds from sale of common stock, net of offering costs	52,112			52,112
Other				(239)	425				(581)
Cumulative effect of change in accounting principle					0
Net loss attributable to stockholders of Overstock.com, Inc.	(63,925)				(63,925)
Net other comprehensive income	8					8
Common stock repurchased through business combination							(643)
Tax withholding upon vesting of restricted stock							(1,346)		0
Proceeds from security token offering, net									0
Net loss attributable to noncontrolling interests	(6,593)								(6,593)
Fair value of noncontrolling interest at acquisition									0
Ending balance at Jun. 30, 2019	199,080	$ 3	0	719,010	(522,397)	(576)	$ (68,746)	127,294	71,786
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Common stock issued for asset purchase				0
Common stock, beginning balance (in shares) at Mar. 31, 2019		37,802,000					3,319,000
Preferred stock, beginning balance (in shares) at Mar. 31, 2019											127,000		0			355,000
Increase (Decrease) in Stockholders' Equity
Shares converted (in shares)											123,000		(123,000)	1,000		(1,000)
Common stock issued upon vesting of restricted stock (in shares)		14,000
Stock Issued During Period, Shares, Purchase of Assets		0
Exercise of stock warrants (in shares)		0
Common stock sold through ATM offering (in shares)		745,000
Common stock repurchased through business combination (in shares)							0
Tax withholding upon vesting of restricted stock (in shares)							3,000
Preferred stock, ending balance (in shares) at Jun. 30, 2019										3,000	3,000	123,000	123,000		356,000	356,000
Common stock, ending balance (in shares) at Jun. 30, 2019		38,561,000					3,322,000
Beginning balance at Mar. 31, 2019				701,877	(497,716)	(580)	$ (68,753)		74,731
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Stock-based compensation to employees and directors				5,171					0
Issuance and exercise of stock warrants				0
Proceeds from sale of common stock, net of offering costs				12,198
Other				(236)	0				0
Cumulative effect of change in accounting principle					0
Net loss attributable to stockholders of Overstock.com, Inc.	(24,681)				(24,681)
Net other comprehensive income	4					4
Common stock repurchased through business combination							0
Tax withholding upon vesting of restricted stock							7		0
Proceeds from security token offering, net									0
Net loss attributable to noncontrolling interests	(2,945)								(2,945)
Fair value of noncontrolling interest at acquisition									0
Ending balance at Jun. 30, 2019	$ 199,080	$ 3	$ 0	719,010	$ (522,397)	$ (576)	$ (68,746)	$ 127,294	$ 71,786
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Common stock issued for asset purchase				$ 0
Common Stock, Shares, Outstanding	35,239,000	35,239,000