COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	1 Months Ended
May 31, 2025 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Future lease payment decrease	$ 10
Loss on termination of lease	1
Decrease in operating lease right of use asset	8
Decrease in operating lease liability	7
Other associated costs	$ 2

Increase (Decrease) In Operating Lease Right Of Use Asset

No definition available.

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- Definition

Lessee, Operating Lease, Liability, To Be Paid, Increase (Decrease).

+ References

No definition available.

+ Details

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Namespace Prefix:	open_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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- Definition

Amount of gain (loss) on termination of lease before expiration of lease term.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479092/842-20-40-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) in obligation for operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (g)(1)
-SubTopic 20
-Topic 842
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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- Definition

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

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