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Subsequent Events Narrative (Details) - Subsequent Event [Member] - 2100 Pennsylvania Avenue [Member] $ in Millions	Jul. 16, 2019 USD ($) ft²
Subsequent Event [Line Items]
Lessee, Finance Lease, Term of Contract	75 years
Net Rentable Area (in sf)	480,000
Prepaid Rent | $	$ 15.0
Term of Lease Signed (in years)	16-year
Square Footage Of Signed Lease	300,000

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Square Footage Of Signed Lease.

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Term of Lease Signed (in years)

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- Definition

Term of lessee's finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-Section 50
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Net rentable area for properties owned.

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Amount of asset related to consideration paid in advance for rent that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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