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Represents the reallocation of equity between limited and general partner.

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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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Noncontrolling Interests - Change in Carrying Value (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 03, 2019	Apr. 30, 2018	Mar. 30, 2018	Jun. 27, 2013	Jan. 22, 2013
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period	$ 32,236	$ 19,207
Reallocation of equity		0	$ 0	$ 0
Allocation of net income		984	520	906
Carrying value at end of the period		$ 32,236	$ 19,207
Tau Operating Partnership
Change in the carrying value of all noncontrolling interests
Number of partnership units issued									317,022
Number of partnership units outstanding		317,022	317,022
Tau Operating Partnership \| Subsequent event
Change in the carrying value of all noncontrolling interests
Number of partnership units redeemed	317,022
Realty Income, L.P.
Change in the carrying value of all noncontrolling interests
Number of partnership units issued		373,797				131,790	242,007	534,546
Number of partnership units outstanding		373,797	88,182
Realty Income, L.P. \| Subsequent event
Change in the carrying value of all noncontrolling interests
Number of partnership units outstanding					373,797
Noncontrolling interests
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period	$ 32,236	$ 19,207	$ 20,249
Reallocation of equity		774	485	543
Redemptions		(5,581)
Shares issued in conjunction with acquisition		18,848
Distributions		(1,996)	(2,047)
Allocation of net income		984	520
Carrying value at end of the period		32,236	19,207	20,249
Noncontrolling interests \| Tau Operating Partnership
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period	13,356	13,322	13,405
Reallocation of equity		572	492
Redemptions		0
Shares issued in conjunction with acquisition		0
Distributions		(837)	(804)
Allocation of net income		299	229
Carrying value at end of the period		13,356	13,322	13,405
Noncontrolling interests \| Realty Income, L.P.
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period	17,912	2,160	2,216
Reallocation of equity		(43)	(26)
Redemptions		(2,829)
Shares issued in conjunction with acquisition		18,848
Distributions		(842)	(224)
Allocation of net income		618	194
Carrying value at end of the period		17,912	2,160	2,216
Noncontrolling interests \| Other Noncontrolling Interests
Change in the carrying value of all noncontrolling interests
Carrying value at beginning of the period	$ 968	3,725	4,628
Reallocation of equity		245	19
Redemptions		(2,752)
Shares issued in conjunction with acquisition		0
Distributions		(317)	(1,019)
Allocation of net income		67	97
Carrying value at end of the period		$ 968	$ 3,725	$ 4,628