Proceeds From Investment In Subsidiary

No definition available.

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Namespace Prefix:	ostk_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_EquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash inflow associated with the sale of 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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

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- Details

Name:	dei_LegalEntityAxis=ostk_GSRCapitalAndMakaraCapitalMember
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SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions		1 Months Ended
SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions	Jan. 18, 2019	Mar. 18, 2019	Dec. 31, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Carrying value of equity method investments			$ 40.1	$ 6.5
tZero.com, Inc. \| Subsequent Event
Subsequent Event [Line Items]
Carrying value of equity method investments	$ 5.8
Proceeds from sale of equity method investments	$ 5.9
GSR Capital and Makara Capital \| Subsequent Event
Subsequent Event [Line Items]
Proceeds from sale of investment		$ 100.0