Number of impaired real estate assets during the period.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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- 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.

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- Definition

Fair value portion of other assets.

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- Definition

Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Fair Value Measurements - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) property	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Fair Value
Net unrealized gain (loss) on derivative designated as effective hedge	$ 22,700	$ 55,000
Gain (loss) expected to be reclassified into interest expense within the next 12 months	24,200
Impairment loss	$ 90,226		$ 25,144
Nonrecurring \| Fair Value
Fair Value
Other assets		$ 0
Commercial Assets
Fair Value
Number of impaired real estate assets \| property	3
Development Parcel
Fair Value
Number of impaired real estate assets \| property	1
2101 L Street \| Level 3 \| Nonrecurring
Fair Value
Estimated fair value	$ 121,300
2101 L Street, 2100 Crystal Drive, 2200 Crystal Drive and Development Parcel \| Nonrecurring
Fair Value
Impairment loss	90,200
2100 Crystal Drive, 2200 Crystal Drive and Development Parcel \| Level 2 \| Nonrecurring
Fair Value
Estimated fair value	$ 56,400
7200 Wisconsin Avenue, RTC-West and a Development Parcel \| Level 2 \| Nonrecurring
Fair Value
Impairment loss			25,100
Estimated fair value			$ 309,000