Sale Of Stock, Number of Shares Issued In Transaction As A Percentage Of Total Shares Issued And Outstanding

No definition available.

Name:	ostk_SaleOfStockNumberofSharesIssuedInTransactionAsAPercentageOfTotalSharesIssuedAndOutstanding
Namespace Prefix:	ostk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Sale Of Stock, Total Consideration Received On Transaction

+ References

No definition available.

+ Details

Name:	ostk_SaleOfStockTotalConsiderationReceivedOnTransaction
Namespace Prefix:	ostk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sale Of Stock, Value Of Securities Received As Consideration

+ References

No definition available.

+ Details

Name:	ostk_SaleOfStockValueOfSecuritiesReceivedAsConsideration
Namespace Prefix:	ostk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sale Of Tokens, Price Per Token

+ References

No definition available.

+ Details

Name:	ostk_SaleOfTokensPricePerToken
Namespace Prefix:	ostk_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ClassOfStockLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireEquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockConsiderationReceivedOnTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_CounterpartyNameAxis=ostk_GSRCapitalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=ostk_TZero.comInc.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=ostk_TZero.comInc.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=ostk_GSRCapitalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

STOCKHOLDERS' EQUITY - GSR Agreement (Details) - USD ($) $ / shares in Units, $ in Millions				6 Months Ended
	Jul. 11, 2019	May 08, 2019	May 06, 2019	Jun. 30, 2019
GSR Capital
Class of Stock [Line Items]
Sale of tokens (in usd per token)			$ 6.67
tZero.com, Inc.
Class of Stock [Line Items]
Number of shares sold in transaction (in shares)		508,710
Number of shares sold in transaction as percentage of total shares issued and outstanding		0.50%
Total consideration received from sale of stock		$ 5.0
Consideration received from sale of stock		1.0
Value of shares received from sale of stock		$ 3.0
tZero.com, Inc. \| GSR Capital
Class of Stock [Line Items]
Cash portion of acquisition price			$ 30.0
Consideration received from sale of stock				$ 1.0
tZero.com, Inc. \| GSR Capital \| Subsequent Event
Class of Stock [Line Items]
Consideration received from sale of stock	$ 1.0