Commercial Paper Program, Maximum Aggregate Capacity

No definition available.

Name:	o_CommercialPaperProgramMaximumAggregateCapacity
Namespace Prefix:	o_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total of all fees that are fixed as a percentage of the amount of the debt facility as a percentage over LIBOR.

+ References

No definition available.

+ Details

Name:	o_LineOfCreditFacilityBasisSpreadAndCommitmentFeeTotal
Namespace Prefix:	o_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility, Contingent Expansion Option, Additional Borrowing Capacity

+ References

No definition available.

+ Details

Name:	o_LineOfCreditFacilityContingentExpansionOptionAdditionalBorrowingCapacity
Namespace Prefix:	o_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the period of time for which extensions are available under a line of credit agreement.

+ References

No definition available.

+ Details

Name:	o_LineOfCreditFacilityExtensionPeriod
Namespace Prefix:	o_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility, Number Of Currencies Allowable

+ References

No definition available.

+ Details

Name:	o_LineOfCreditFacilityNumberOfCurrenciesAllowable
Namespace Prefix:	o_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of extensions available at the option of the Company.

+ References

No definition available.

+ Details

Name:	o_LineOfCreditFacilityNumberOfExtensions
Namespace Prefix:	o_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13)(2))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: 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(19)(a)(3))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_CommercialPaper
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section S45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68176171&loc=SL68176184-208336

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the 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))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ References

+ Details

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

- Definition

Weighted average interest rate of short-term debt outstanding calculated over time.

+ References

No definition available.

+ Details

Name:	us-gaap_ShortTermDebtWeightedAverageInterestRateOverTime
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_CommercialPaperMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	o_DebtInstrumentMaturityPeriodAxis=o_DebtInstrumentMaturityPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	o_DebtInstrumentMaturityPeriodAxis=o_DebtInstrumentMaturityPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	o_DebtInstrumentMaturityPeriodAxis=o_DebtInstrumentMaturityPeriodThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Revolving Credit Facility and Commercial Paper Program (Details)	3 Months Ended
	Mar. 31, 2021 USD ($) extension currency	Mar. 31, 2020	Dec. 31, 2020 USD ($)
Credit facility
Credit facility origination costs	$ 6,849,000		$ 7,705,000
Maximum aggregate capacity of commercial paper program	1,000,000,000.0
Commercial paper borrowings outstanding	675,000,000.0		0
Unsecured debt \| Revolving credit facility
Credit facility
Maximum borrowing capacity	$ 3,000,000,000.0
Number of extensions \| extension	2
Term of extension option	6 months
Number of currencies allowable per facility \| currency	14
Credit facility expansion option	$ 1,000,000,000.0
Current borrowing capacity	3,000,000,000.0		3,000,000,000.0
Outstanding balance	$ 0		0
Weighted average borrowing rate during the period (as a percent)	0.80%	2.10%
Unsecured debt \| Revolving credit facility \| Other assets, net
Credit facility
Credit facility origination costs	$ 6,800,000		$ 7,700,000
Unsecured debt \| Revolving credit facility \| LIBOR
Credit facility
Basis spread on variable rate (as a percent)	0.775%
Commitment fee (as a percent)	0.125%
All-in drawn variable interest rate (as a percent)	0.90%
Commercial paper
Credit facility
Weighted average borrowing rate during the period (as a percent)	0.30%
Weighted average interest rate at the end of the period (as a percent)	0.20%
Commercial paper \| Maturity period one
Credit facility
Commercial paper borrowings outstanding	$ 50,000,000.0
Maturity date	Apr. 09, 2021
Commercial paper \| Maturity period two
Credit facility
Commercial paper borrowings outstanding	$ 240,000,000.0
Maturity date	Apr. 23, 2021
Commercial paper \| Maturity period three
Credit facility
Commercial paper borrowings outstanding	$ 385,000,000.0
Maturity date	May 12, 2021