Debt Instrument Contractual Facility Borrowing Capacity

No definition available.

Name:	rdi_DebtInstrumentContractualFacilityBorrowingCapacity
Namespace Prefix:	rdi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Net increase or decrease in the carrying amount of the debt instrument for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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

Debt (U.S. Corporate Office Term Loan) (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended	12 Months Ended
	Jun. 26, 2017	Dec. 13, 2016	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Contractual facility			$ 290,879	$ 252,929
U.S. Corporate Office Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument term		10 years
Contractual facility		$ 8,400	$ 9,437	$ 9,495
Interest rate	4.44%	4.64%
Debt increase	$ 1,500