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v3.19.3.a.u2

Significant Accounting Policies - Concentrations of Credit Risk/Reclassification (Details) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 31, 2020 | Dec. 31, 2019 Tenant agreement | Dec. 31, 2018 | Dec. 31, 2017
Annualized rent | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Number of tenants (tenants) | Tenant |  | 1 |  |
Maximum percentage of annualized rent for any one tenant not individually disclosed (percent) (more than) |  | 5.00% |  |
Annualized rent | 11 Madison Avenue | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 7.60% | 7.40% | 7.00%
Annualized rent | 1185 Avenue of the Americas | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 7.40% | 6.70% | 7.10%
Annualized rent | 420 Lexington Avenue | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 6.60% | 6.00% | 6.00%
Annualized rent | 1515 Broadway | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 6.10% | 6.50% | 7.10%
Annualized rent | One Madison Ave | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 6.00% | 5.80% | 5.60%
Annualized rent | East 220 Street 42 | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 5.50% |  |
Collective bargaining arrangements | Workforce concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 70.10% |  |
Number of collective bargaining agreements | agreement |  | 6 |  |
Collective bargaining arrangements expiring in December 2019 | Workforce concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 2.10% |  |
Tenant 1 | Annualized rent | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) |  | 8.20% |  |
Subsequent Event | Credit Suisse | Annualized rent | Customer concentration |  |  |  |
Concentration of Credit Risk |  |  |  |
Percentage of concentration (percent) | 3.30% |  |  |

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