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Noncontrolling Interests on the Company's Consolidated Financial Statements - Additional Information (Details) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Sep. 30, 2020 USD ($) shares $ / shares | Sep. 30, 2019 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) shares $ / shares | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) shares
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Redemption and conversion of common units | $ | $ 0 | $ (54) | $ (1,536) | $ (25,791) |  |  |
Net income | $ | 802 | 1,719 |  |  | $ 10,073 | $ 12,306 |
Accumulated other comprehensive loss allocation | $ | 317 | (607) |  |  | (2,664) | (2,869) |
Partnership Interest |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Balance at beginning of period | $ |  |  | 409,862 | 387,805 | 409,862 | 387,805 | $ 387,805
Distributions | $ |  |  |  |  | (8,857) |  | (14,729)
Issuance of common units | $ |  |  |  |  | 7,976 |  | 19,403
Redemption and conversion of common units | $ |  |  |  |  | (27,657) |  | (27,962)
Net income | $ |  |  |  |  | 10,073 |  | 13,301
Accumulated other comprehensive loss allocation | $ |  |  |  |  | (2,664) |  | (2,276)
Fair value adjustment | $ |  |  |  |  | (35,253) |  | 34,320
Balance at end of period | $ | $ 353,480 |  |  |  | $ 353,480 |  | $ 409,862
SL Green Operating Partnership |  |  |  |  |  |  |
Organization |  |  |  |  |  |  |
Number of units of operating partnership owned by the noncontrolling interest unit holders (shares) | 4,027,317 |  |  |  | 4,027,317 |  | 4,195,875
Shares of common stock reserved for issuance upon redemption of units of limited partnership interest in operating partnership (shares) | 4,027,317 |  |  |  | 4,027,317 |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Redemption and conversion of common units | $ | $ 0 | (54) | $ (1,536) | $ (25,791) |  |  |
Accumulated other comprehensive loss allocation | $ | $ 317 | $ (607) |  |  | $ (2,664) | $ (2,869) |
SL Green Operating Partnership | 3.50% Series A |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 3.50% |  |
Preferred units, shares authorized (in shares) | 109,161 |  |  |  | 109,161 |  |
Number of preferred units issued (in shares) | 109,161 |  |  |  | 109,161 |  |
Number of Units Outstanding (in shares) | 109,161 |  |  |  | 109,161 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 35.0000 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 1,000.00 |  |  |  | 1,000.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 0 |  |  |  | $ 0 |  |
Number of company common stock issued on conversion of Series B preferred units |  |  |  |  | 6.71348 |  |
SL Green Operating Partnership | 7.00% Series F |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 7.00% |  |
Preferred units, shares authorized (in shares) | 60 |  |  |  | 60 |  |
Number of preferred units issued (in shares) | 60 |  |  |  | 60 |  |
Number of Units Outstanding (in shares) | 60 |  |  |  | 60 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 70.0000 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 1,000.00 |  |  |  | 1,000.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 29.12 |  |  |  | $ 29.12 |  |
SL Green Operating Partnership | 4.50% Series G |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 4.50% |  |
Preferred units, shares authorized (in shares) | 1,902,000 |  |  |  | 1,902,000 |  |
Number of preferred units issued (in shares) | 1,902,000 |  |  |  | 1,902,000 |  |
Number of Units Outstanding (in shares) | 863,972 |  |  |  | 863,972 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 1.1250 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 88.50 |  |  |  | $ 88.50 |  |
Number of company common stock issue on redemption of operation partnership common units |  |  |  |  | 1 |  |
SL Green Operating Partnership | 3.50% Series K |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 3.50% |  |
Preferred units, shares authorized (in shares) | 700,000 |  |  |  | 700,000 |  |
Number of preferred units issued (in shares) | 563,954 |  |  |  | 563,954 |  |
Number of Units Outstanding (in shares) | 341,677 |  |  |  | 341,677 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 0.8750 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 134.67 |  |  |  | $ 134.67 |  |
SL Green Operating Partnership | 4.00% Series L |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 4.00% |  |
Preferred units, shares authorized (in shares) | 500,000 |  |  |  | 500,000 |  |
Number of preferred units issued (in shares) | 378,634 |  |  |  | 378,634 |  |
Number of Units Outstanding (in shares) | 372,634 |  |  |  | 372,634 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 1.0000 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 0 |  |  |  | $ 0 |  |
SL Green Operating Partnership | 3.75% Series M |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 3.75% |  |
Preferred units, shares authorized (in shares) | 1,600,000 |  |  |  | 1,600,000 |  |
Number of preferred units issued (in shares) | 1,600,000 |  |  |  | 1,600,000 |  |
Number of Units Outstanding (in shares) | 96,357 |  |  |  | 96,357 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 0.9375 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 0 |  |  |  | $ 0 |  |
SL Green Operating Partnership | 4.00% Series P |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 4.00% |  |
Preferred units, shares authorized (in shares) | 200,000 |  |  |  | 200,000 |  |
Number of preferred units issued (in shares) | 200,000 |  |  |  | 200,000 |  |
Number of Units Outstanding (in shares) | 200,000 |  |  |  | 200,000 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 1.0000 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 0 |  |  |  | $ 0 |  |
SL Green Operating Partnership | 3.50% Series Q |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 3.50% |  |
Preferred units, shares authorized (in shares) | 268,000 |  |  |  | 268,000 |  |
Number of preferred units issued (in shares) | 268,000 |  |  |  | 268,000 |  |
Number of Units Outstanding (in shares) | 268,000 |  |  |  | 268,000 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 0.8750 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 148.95 |  |  |  | $ 148.95 |  |
SL Green Operating Partnership | 3.50% Series R |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 3.50% |  |
Preferred units, shares authorized (in shares) | 400,000 |  |  |  | 400,000 |  |
Number of preferred units issued (in shares) | 400,000 |  |  |  | 400,000 |  |
Number of Units Outstanding (in shares) | 400,000 |  |  |  | 400,000 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 0.8750 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 154.89 |  |  |  | $ 154.89 |  |
SL Green Operating Partnership | 4.00% Series S |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 4.00% |  |
Preferred units, shares authorized (in shares) | 1,077,280 |  |  |  | 1,077,280 |  |
Number of preferred units issued (in shares) | 1,077,280 |  |  |  | 1,077,280 |  |
Number of Units Outstanding (in shares) | 1,077,280 |  |  |  | 1,077,280 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 1.0000 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 0 |  |  |  | $ 0 |  |
SL Green Operating Partnership | 3.50% Series V |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Dividend rate preferred units (as a percent) |  |  |  |  | 3.50% |  |
Preferred units, shares authorized (in shares) | 40,000 |  |  |  | 40,000 |  |
Number of preferred units issued (in shares) | 40,000 |  |  |  | 40,000 |  |
Number of Units Outstanding (in shares) | 40,000 |  |  |  | 40,000 |  |
Annual dividends on preferred units (in dollars per share) | $ / shares |  |  |  |  | $ 0.8750 |  |
Liquidation preference of preferred units (in dollars per share) | $ / shares | $ 25.00 |  |  |  | 25.00 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 0 |  |  |  | $ 0 |  |
SL Green Operating Partnership | Series W |  |  |  |  |  |  |
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership |  |  |  |  |  |  |
Preferred units, shares authorized (in shares) | 1 |  |  |  | 1 |  |
Number of preferred units issued (in shares) | 1 |  |  |  | 1 |  |
Number of Units Outstanding (in shares) | 1 |  |  |  | 1 |  |
Operating partnership common stock value use for conversion of preferred units (in dollars per share) | $ / shares | $ 0 |  |  |  | $ 0 |  |
Preferred stock, dividend, multiplier per common unit distribution |  |  |  |  | 1,350 |  |
Operating Partnership | SL Green Operating Partnership |  |  |  |  |  |  |
Organization |  |  |  |  |  |  |
Noncontrolling interest in the operating partnership (as a percent) | 5.23% |  |  |  | 5.23% |  | 5.03%

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- Definition The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer. + 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(27)(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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