Mortgage Notes Payable, Net - Multi-Tenant Mortgage Loan IV (Details) $ in Millions	Apr. 12, 2019 USD ($) sate leased_office_and_industrial_property
Multi-Tenant Mortgage Loan IV \| Column Financial, Inc. and Societe Generale Financial Corporation
Debt Instrument [Line Items]
Collateral, number of leased offices and industrial properties \| leased_office_and_industrial_property	16
Multi-Tenant Mortgage Loan IV \| Mortgage notes payable \| Column Financial, Inc. and Societe Generale Financial Corporation
Debt Instrument [Line Items]
Proceeds from loans borrowed	$ 97.5
Repayments of debt	$ 90.0
Interest rate	4.489%
Multi-Tenant Mortgage Loan \| Mortgage notes payable
Debt Instrument [Line Items]
Number of states in which mortgaged properties are located (state) \| sate	12

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