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Significant Accounting Policies - Acquired Unfavorable Real Estate Leases and Amortization (Details) - Acquired unfavorable real estate leases - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Acquired Unfavorable Real Estate Leases and Amortization |  |  |
Amortization | $ 500 | $ 900 | $ 1,300
Estimated annual amortization for succeeding five years |  |  |
2022 | 161 |  |
2023 | 104 |  |
2024 | 93 |  |
2025 | 60 |  |
2026 | 31 |  |
2027 and thereafter | $ 79 |  |
Minimum |  |  |
Acquired Unfavorable Real Estate Leases and Amortization |  |  |
Term of lease | 64 months |  |
Maximum |  |  |
Acquired Unfavorable Real Estate Leases and Amortization |  |  |
Term of lease | 151 months |  |

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- Definition Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References No definition available. + Details
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- Definition Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References No definition available. + Details
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