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Fair Value Measurements (Details) - USD ($) $ in Thousands | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2021 | Jul. 31, 2021 | Dec. 31, 2020
Fair Value of Financial Instruments |  |  |
Marketable securities available-for-sale | $ 24,355 |  | $ 28,570
Interest rate cap and swap agreements (included in Other assets) | 97 |  | 28
Debt and preferred equity investments | 1,052,110 |  | 1,076,542
220 East 42nd Street |  |  |
Fair Value of Financial Instruments |  |  |
Ownership interest disposed |  | 49.00% |
Carrying Value |  |  |
Fair Value of Financial Instruments |  |  |
Debt and preferred equity investments | 1,052,110 |  | 1,076,542
Fixed rate debt | 3,577,313 |  | 3,135,572
Variable rate debt | 572,581 |  | 1,827,677
Total | 4,149,894 |  | 4,963,249
Fair Value |  |  |
Fair Value of Financial Instruments |  |  |
Marketable securities available-for-sale | 24,355 |  | 28,570
Total | 4,221,525 |  | 5,059,815
Estimated fair value of debt and preferred equity investments, low end of range | 900,000 |  | 1,000,000
Estimated fair value of debt and preferred equity investments, high end of range | 1,100,000 |  | 1,100,000
Level 1 |  |  |
Fair Value of Financial Instruments |  |  |
Interest rate cap and swap agreements (included in Other assets) | 0 |  | 0
Level 2 |  |  |
Fair Value of Financial Instruments |  |  |
Interest rate cap and swap agreements (included in Other assets) | 97 |  | 28
Level 3 |  |  |
Fair Value of Financial Instruments |  |  |
Marketable securities available-for-sale | 0 |  | 0
Interest rate cap and swap agreements (included in Other assets) | 0 |  | 0
Level 3 | Fair Value |  |  |
Fair Value of Financial Instruments |  |  |
Fixed rate debt | 3,650,924 |  | 3,237,075
Variable rate debt | 570,601 |  | 1,822,740
Equity Securities | Level 1 |  |  |
Fair Value of Financial Instruments |  |  |
Marketable securities available-for-sale | 0 |  | 0
Commercial mortgage-backed securities |  |  |
Fair Value of Financial Instruments |  |  |
Marketable securities available-for-sale | 24,355 |  | 28,570
Commercial mortgage-backed securities | Level 2 |  |  |
Fair Value of Financial Instruments |  |  |
Marketable securities available-for-sale | 24,355 |  | 28,570
220 East 42nd Street | 220 East 42nd Street |  |  |
Fair Value of Financial Instruments |  |  |
Ownership percentage deconsolidated |  | 51.00% |
Investment fair value adjustment | 206,800 |  |
Accrued Interest Payable and Other |  |  |
Fair Value of Financial Instruments |  |  |
Interest rate cap and swap agreements (included in Other liabilities) | 40,737 |  | 61,217
Accrued Interest Payable and Other | Level 1 |  |  |
Fair Value of Financial Instruments |  |  |
Interest rate cap and swap agreements (included in Other liabilities) | 0 |  | 0
Accrued Interest Payable and Other | Level 2 |  |  |
Fair Value of Financial Instruments |  |  |
Interest rate cap and swap agreements (included in Other liabilities) | 40,737 |  | 61,217
Accrued Interest Payable and Other | Level 3 |  |  |
Fair Value of Financial Instruments |  |  |
Interest rate cap and swap agreements (included in Other liabilities) | $ 0 |  | $ 0

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