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Represents the reallocation of equity between limited and general partner.

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Partnership Units, Number Issued During Period

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Number of partnership units outstanding.

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The cash outflow or inflow increase (decrease) in distribution due to real estate partnership based upon payments and accruals.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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Noncontrolling Interests - Change in Carrying Value (Details) - USD ($) $ in Thousands					12 Months Ended
	Mar. 28, 2019	Apr. 30, 2018	Mar. 30, 2018	Jan. 22, 2013	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period					$ 29,702
Reallocation of equity					0	$ 0	$ 0
Redemptions						(21,123)	(2,752)
Additions to noncontrolling interest					3,168	11,370	18,848
Allocation of net income					1,020	996	984
Carrying value at end of the period					$ 32,247	$ 29,702
Tau Operating Partnership units
Change in the carrying value of all noncontrolling interests
Number of partnership units issued (in units)				317,022
Number of partnership units outstanding (in units)					0	0
Realty Income, L.P. units
Change in the carrying value of all noncontrolling interests
Additions to noncontrolling interest						$ 6,300	$ 18,800
Number of partnership units issued (in units)	89,322	131,790	242,007			89,322	373,797
Number of partnership units outstanding (in units)					463,119	463,119
Noncontrolling interests
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period					$ 29,702	$ 32,236
Reallocation of equity					(47)	653	$ 774
Redemptions						(14,257)	(5,581)
Additions to noncontrolling interest					3,168	11,370	18,848
Distributions					(1,596)	(1,296)
Allocation of net income					1,020	996
Carrying value at end of the period					32,247	29,702	32,236
Noncontrolling interests \| Tau Operating Partnership units
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period					0	13,356
Reallocation of equity					0	0
Redemptions						(13,356)
Additions to noncontrolling interest					0	0
Distributions					0	0
Allocation of net income					0	0
Carrying value at end of the period					0	0	13,356
Noncontrolling interests \| Realty Income, L.P. units
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period					24,596	17,912
Reallocation of equity					(47)	653
Redemptions						0
Additions to noncontrolling interest					0	6,286
Distributions					(1,297)	(1,219)
Allocation of net income					848	964
Carrying value at end of the period					24,100	24,596	17,912
Noncontrolling interests \| Other Noncontrolling Interests
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period					5,106	968
Reallocation of equity					0	0
Redemptions						(901)
Additions to noncontrolling interest					3,168	5,084
Distributions					(299)	(77)
Allocation of net income					172	32
Carrying value at end of the period					$ 8,147	$ 5,106	$ 968