Real Estate Property Sale Price

No definition available.

Name:	rdi_RealEstatePropertySalePrice
Namespace Prefix:	rdi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The average effective interest rate during the reporting period.

+ References

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-Publisher FASB
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+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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+ Details

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

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount for notes payable (written promise to pay), due to related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount of an option or options to acquire real property.

+ References

No definition available.

+ Details

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

- Definition

The cash outflow for a borrowing supported by a written promise to pay an obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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.

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=rdi_ManukauNzMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=rdi_ShadowViewLandAndFarmingLlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=rdi_FortyFourUnionSquareMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_ConstructionLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=rdi_SuttonHillCapitalLlcMember
Namespace Prefix:
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Subsequent Events (Narrative) (Details) $ in Millions	Mar. 26, 2021 USD ($)	Mar. 05, 2021 USD ($)	Mar. 29, 2021 USD ($)	Mar. 04, 2021 USD ($)	Mar. 04, 2021 NZD ($)	Dec. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)
Subsequent Event [Member]
Subsequent Event [Line Items]
Notes payable to related party		$ 2,000,000.0
Interest expense		$ 1,181
Loan rate		4.50%
Coachella, CA [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Sale price		$ 11,000,000.0
Manukau, NZ [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Sale price				$ 56,100,000	$ 77.2
Shadow View Land And Farming, LLC [Member]
Subsequent Event [Line Items]
Noncontrolling interests						50.00%
44 Union Square [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Repayment of notes payable	$ 40,600,000
44 Union Square [Member] \| Subsequent Event [Member] \| Construction Loans [Member]
Subsequent Event [Line Items]
Repayment of notes payable	$ 40,600,000
Village East Cinema [Member] \| Sutton Hill Capital, LLC [Member]
Subsequent Event [Line Items]
Purchase option						$ 5,900,000	$ 5,900,000
Village East Cinema [Member] \| Subsequent Event [Member] \| Sutton Hill Capital, LLC [Member]
Subsequent Event [Line Items]
Purchase option			$ 5,900,000