Common Stock Incentive Plan	6 Months Ended
Common Stock Incentive Plan	Jun. 30, 2021
Share-based Payment Arrangement [Abstract]
Common Stock Incentive Plan	Common Stock Incentive Plan In March 2021, our Board of Directors adopted, and in May 2021, stockholders approved, the Realty Income 2021 Incentive Award Plan, or 2021 Plan, to enable us to motivate, attract and retain the services of directors, employees and consultants, considered essential to our long-term success. The 2021 Plan offers our directors, employees and consultants an opportunity to own our stock and/or rights that will reflect our growth, development and financial success. Under the terms of the 2021 Plan, the aggregate number of shares of our common stock subject to options, stock purchase rights, or SPR, stock appreciation rights, or SAR, and other awards, will be no more 8,924,231 shares. The maximum number of shares that may be subject to options, SPR, SAR and other awards granted under the plan to any individual in any calendar year may not exceed 3,200,000, and the maximum aggregate amount of cash that may be paid in cash during any calendar year with respect to one or more shares payable in cash shall be $10.0 million. The 2021 Plan replaced the Realty Income Corporation 2012 Incentive Award Plan, or the 2012 Plan, which was set to expire in March 2022. No further awards will be granted under the 2012 Plan. The disclosures below incorporate activity for both the 2012 Plan and the 2021 Plan. The amount of share-based compensation costs recognized in general and administrative expense on our consolidated statements of income and comprehensive income was $4.5 million during the three months ended June 30, 2021, $4.9 million during the three months ended June 30, 2020, $8.2 million during the six months ended June 30, 2021, and $10.4 million during the six months ended June 30, 2020 (including $1.8 million of accelerated share-based compensation costs for our former Chief Financial Officer ("CFO")). Upon the departure of our former CFO in March 2020, we incurred a severance charge of $3.5 million, consisting of $1.6 million of cash, $1.8 million related to share-based compensation expense and $58,000 of professional fees. A. Restricted Stock During the six months ended June 30, 2021, we granted 112,498 shares of common stock under the 2012 and 2021 Plans. This included 36,000 total shares of restricted stock granted to the independent members of our Board of Directors in connection with our annual awards in May 2021, 24,000 shares of which vested immediately and 12,000 shares of which vest in equal parts over a three-year service period. Our restricted stock awards granted to employees vest in equal parts over a four-year service period. As of June 30, 2021, the remaining unamortized share-based compensation expense related to restricted stock totaled $11.0 million, which is being amortized on a straight-line basis over the service period of each applicable award. The amount of share-based compensation is based on the fair value of the stock at the grant date. We define the grant date as the date the recipient and Realty Income have a mutual understanding of the key terms and conditions of the award, and the recipient of the grant begins to benefit from, or be adversely affected by, subsequent changes in the price of the shares. B. Performance Shares and Restricted Stock Units During the six months ended June 30, 2021, we granted 157,341 performance shares, as well as dividend equivalent rights, to our executive officers, of which 9,621 shares were subsequently forfeited, leaving 147,720 of the 2021 grants outstanding at June 30, 2021. The performance shares are earned based on our Total Shareholder Return (TSR) performance relative to select industry indices and peer groups as well as achievement of certain operating metrics, and vest 50% on the first and second January 1 after the end of the three-year performance period, subject to continued service. During the six months ended June 30, 2021, we also granted 17,285 restricted stock units, all of which vest over a four-year service period. These restricted stock units have the same economic rights as shares of restricted stock. As of June 30, 2021, the remaining share-based compensation expense related to the performance shares and restricted stock units totaled $15.5 million. The fair value of the performance shares were estimated on the date of grant using a Monte Carlo Simulation model. The performance shares are being recognized on a tranche-by-tranche basis over the service period. The amount of share-based compensation for the restricted stock units is based on the fair value of our common stock at the grant date. The expense amortization period for restricted stock units is the lesser of the four-year service period or the period over which the awardee reaches the qualifying retirement age. For employees who have already met the qualifying retirement age, restricted stock units are fully expensed at the grant date.