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Fair Value Measurements - Non-recurring Fair Value Measurements for Impairment (Details)	3 Months Ended
	Mar. 31, 2021 $ / ft² yr realEstateProperty
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of properties impaired | realEstateProperty	2
2200 Channahon Road | Expected selling price per square foot
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Expected selling price per square foot | $ / ft²	8.30
2200 Channahon Road | Estimated hold period
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Expected selling price per square foot | yr	1
Houston Westway I | Expected selling price per square foot
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Expected selling price per square foot | $ / ft²	72.90
Houston Westway I | Estimated hold period
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Expected selling price per square foot | yr	1

X

- Definition

Number of Impaired Properties

+ References

No definition available.

+ Details

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X

- Definition

Real Estate Property, Measurement Input

+ References

No definition available.

+ Details

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Balance Type:	na
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X

- Definition

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.

+ References

No definition available.

+ Details

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X

- Details

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Namespace Prefix:
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X

- Details

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X

- Details

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X

- Details

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