Common Stock, Conversion, Number of New Shares Issued Upon Conversion

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Face amount or stated value per share of common stock.

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Number of shares issued for each share of convertible preferred stock that is converted.

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Costs of sales and operating expenses for the period incurred from transactions with related parties.

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Amount of transactions with related party during the financial reporting period.

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Commitments and Contingencies Commitments (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($) $ / shares	Dec. 31, 2016 USD ($)
Business Acquisition, Contingent Consideration [Line Items]
Common stock, par value (in USD per share) \| $ / shares		$ 0.001	$ 0.001
Asset management fees to affiliates		$ 0	$ 8,027	$ 6,413
Upon merger
Business Acquisition, Contingent Consideration [Line Items]
Common stock, par value (in USD per share) \| $ / shares	$ 0.001
Number of new shares to be received upon conversion	1
Number of shares/units to be received upon conversion \| shares	1
Upon merger \| Griffin Capital Essential Asset REIT, Inc.
Business Acquisition, Contingent Consideration [Line Items]
Common stock, par value (in USD per share) \| $ / shares	$ 0.001
Number of new shares to be received upon conversion	1.04807
Termination fee under Merger Agreement \| Upon merger
Business Acquisition, Contingent Consideration [Line Items]
Termination fee	$ 52,200
Termination fee under Merger Agreement \| Upon merger \| Griffin Capital Essential Asset REIT, Inc.
Business Acquisition, Contingent Consideration [Line Items]
Termination fee	$ 52,200
Merger Agreement - Capitalized Costs
Business Acquisition, Contingent Consideration [Line Items]
Termination fee		$ 1,900