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SECURED AND UNSECURED DEBT, NET - Narrative (Details) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Feb. 28, 2021 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) property loan | Jun. 30, 2020 USD ($) | Jan. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Jul. 31, 2020 USD ($) | Feb. 29, 2020
Secured Debt |  |  |  |  |  |  |  |  |
Secured debt amount which encumbers real estate owned based upon book value |  | $ 1,700,000 |  | $ 1,700,000 |  |  |  |  |
Percentage of secured debt which encumbers real estate owned based upon book value |  | 12.60% |  | 12.60% |  |  |  |  |
Secured debt amount of real estate owned which is unencumbered |  | $ 11,900,000 |  | $ 11,900,000 |  |  |  |  |
Percentage of secured debt of real estate owned which is unencumbered |  | 87.40% |  | 87.40% |  |  |  |  |
Long-term Debt |  | $ 5,447,279 |  | $ 5,447,279 |  |  |  |  |
Extinguishment of debt costs |  |  |  | 40,769 |  |  |  |  |
Unamortized net premium |  | 29,200 |  | 29,200 |  |  | $ 12,900 |  |
300 Home Operating Community in Franklin |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | $ 51,800 |  |  |
Unamortized net premium |  |  |  |  |  | $ 6,600 |  |  |
Unsecured Debt |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Long-term Debt |  | 4,412,962 |  | $ 4,412,962 |  |  |  |  |
Basis points added to to variable rate |  |  |  | 90.00% |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Long-term Debt |  | 1,034,317 |  | $ 1,034,317 |  |  |  |  |
Fixed Rate Debt |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Number of mortgage loans payable assumed | loan |  |  |  | 3 |  |  |  |  |
Long-term Debt |  | 183,300 |  | $ 183,300 |  |  |  |  |
Long term debt fair value |  | $ 201,300 |  | $ 201,300 |  |  |  |  |
Number of operating properties acquired | property |  |  |  | 3 |  |  |  |  |
Fixed Rate Debt | Mortgages Note Payable | Minimum |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Notes payable maximum interest rates range |  | 2.62% |  | 2.62% |  |  |  |  |
Fixed Rate Debt | Mortgages Note Payable | Maximum |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Notes payable maximum interest rates range |  | 4.39% |  | 4.39% |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 4.00% Medium-Term Note due October 2025 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Repayments of outstanding borrowing | $ 300,000 |  |  |  |  |  |  |  |
Stated interest rate | 4.00% | 4.00% |  | 4.00% |  |  | 4.00% |  |
Fixed Rate Debt | Unsecured Debt | 4.00% Medium-Term Note due October 2025 | Interest expense |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Extinguishment of debt costs | $ 42,000 |  |  |  |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 2.95% Medium-Term Note due September 2026 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Long-term Debt |  | $ 300,000 |  | $ 300,000 |  |  | $ 300,000 |  |
Stated interest rate |  | 2.95% |  | 2.95% |  |  | 2.95% |  |
Portion of medium term note subject to interest rate swaps |  | $ 100,000 |  | $ 100,000 |  |  |  |  |
All-in weighted average interest rate |  | 2.89% |  | 2.89% |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 3.50 Medium-Term Note due July 2027 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Stated interest rate |  | 3.50% |  | 3.50% |  |  | 3.50% |  |
Portion of medium term note subject to interest rate swaps |  | $ 200,000 |  | $ 200,000 |  |  |  |  |
All-in weighted average interest rate |  | 4.03% |  | 4.03% |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 4.40% Medium-Term Notes due January 2029 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Principal outstanding |  |  |  |  |  |  |  | $ 300,000 |
Stated interest rate |  | 4.40% |  | 4.40% |  |  | 4.40% |  |
Portion of medium term note subject to interest rate swaps |  | $ 150,000 |  | $ 150,000 |  |  |  |  |
All-in weighted average interest rate |  | 4.27% |  | 4.27% |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 3.20% Medium-Term Notes due January 2030 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Stated interest rate |  | 3.20% |  | 3.20% |  |  | 3.20% |  |
All-in weighted average interest rate |  |  |  |  |  |  |  |  | 3.32%
Fixed Rate Debt | Unsecured Debt | 3.00% Medium-Term Notes due August 2031 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Stated interest rate |  | 3.00% |  | 3.00% |  |  | 3.00% |  |
All-in weighted average interest rate |  | 3.01% |  | 3.01% |  |  |  |  |
Debt |  | $ 150,000 |  | $ 150,000 |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 2.10% Medium Term Note Due August 2032 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Stated interest rate |  | 2.10% |  | 2.10% |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 2.10% Medium-Term Note due June 2033 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Stated interest rate | 2.10% | 2.10% |  | 2.10% |  |  | 2.10% |  |
Medium-term notes | $ 300,000 |  |  |  |  |  |  |  |
Percentage of principal amount at issuance | 99.592 |  |  |  |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 3.10% senior unsecured notes due 2034 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
All-in weighted average interest rate |  | 3.13% |  | 3.13% |  |  |  |  |
Fixed Rate Debt | Unsecured Debt | 1.90% Medium-Term Notes due March 2033 |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Stated interest rate |  | 1.90% |  | 1.90% |  |  | 1.90% |  |
Fixed Rate Debt | Secured Debt |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Long-term Debt |  | $ 1,007,317 |  | $ 1,007,317 |  |  |  |  |
Fixed Rate Debt | Secured Debt | Mortgages Note Payable |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Long-term Debt |  | 1,032,977 |  | 1,032,977 |  |  | $ 835,215 |  |
Fixed Rate Debt | Debt Assumed As Part of Acquisition | Mortgages Note Payable |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Amortization of debt discount (Premium) |  | 1,000 | $ 2,500 | 1,700 | $ 5,100 |  |  |  |
Variable Rate Debt | Secured Debt |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Long-term Debt |  | 27,000 |  | 27,000 |  |  |  |  |
Variable Rate Debt | Tax-exempt secured notes payable | Mortgages Note Payable |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Principal outstanding |  | $ 27,000 |  | $ 27,000 |  |  |  |  |
Variable Rate Debt | Tax-exempt secured notes payable | Mortgages Note Payable |  |  |  |  |  |  |  |  |
Secured Debt |  |  |  |  |  |  |  |  |
Notes payable maximum interest rates range |  | 0.73% |  | 0.73% |  |  |  |  |

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