XML 114 R97.htm IDEA: XBRL DOCUMENT
v3.22.4

SHARE-BASED AWARDS - Stock-Based Compensation Expense (Details) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) marketConditionAward | Dec. 31, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock-based compensation expense |  | $ 171 | $ 536 | $ 38
Market Condition Award |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Reversal of stock-based compensation expense | $ 57 |  |  |
Number of awards with market conditions satisfied | marketConditionAward |  |  | 2 |
Accelerated recognition of stock-based compensation expense |  | 0 | $ 2 |
Market Condition Award | Executive Officer |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock-based compensation expense |  | (13) | $ 290 | $ 20
Unvested Stock Options and Restricted Shares |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Unamortized stock-based compensation | $ 383 | $ 383 |  |
Unamortized stock-based compensation period (in years) |  | 2 years 3 months 18 days |  |

X
- Definition Share-based Payment Arrangement, Expense, Accelerated Recognition + References No definition available. + Details
Name: | open_ShareBasedPaymentArrangementExpenseAcceleratedRecognition
Namespace Prefix: | open_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Share-based Payment Arrangement, Expense, Reversal + References No definition available. + Details
Name: | open_ShareBasedPaymentArrangementExpenseReversal
Namespace Prefix: | open_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Share-based Payment Arrangement, Number Of Awards With Satisfied Market Conditions + References No definition available. + Details
Name: | open_ShareBasedPaymentArrangementNumberOfAwardsWithSatisfiedMarketConditions
Namespace Prefix: | open_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
Name: | us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
Name: | us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
Name: | us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AwardTypeAxis=open_MarketConditionAwardMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_TitleOfIndividualAxis=srt_ExecutiveOfficerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=open_UnvestedStockOptionsAndRestrictedSharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |