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Leases (Lessee Arrangements) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($) Lease
Lessee, Lease, Description [Line Items] |
Lessee, Right-of-use asset | $ 81.0
Minimum | Land Leases |
Lessee, Lease, Description [Line Items] |
Lessee, Remaining term of contract | 28 years
Maximum | Land Leases |
Lessee, Lease, Description [Line Items] |
Lessee, Remaining term of contract | 95 years
Washington DC |
Lessee, Lease, Description [Line Items] |
Lessee, Right-of-use asset | $ 10.1
Lessee, Remaining term of contract | 79 years
Lessee, Number of lease contracts | Lease | 2
Baltimore, Maryland |
Lessee, Lease, Description [Line Items] |
Lessee, Right-of-use asset | $ 6.5
Lessee, Remaining term of contract | 28 years
Optional renewal term | 49 years
Phoenix, Arizona |
Lessee, Lease, Description [Line Items] |
Lessee, Right-of-use asset | $ 6.5
Lessee, Remaining term of contract | 4 years
Optional renewal term | 5 years
Stevens Investors, LLC | Washington DC |
Lessee, Lease, Description [Line Items] |
Lessee, Right-of-use asset | $ 37.8
Lessee, Remaining term of contract | 95 years
LW Redstone Company, LLC | Huntsville, Alabama |
Lessee, Lease, Description [Line Items] |
Lessee, Right-of-use asset | $ 11.3
Lessee, Number of lease contracts | Lease | 15
Optional renewal term | 25 years
LW Redstone Company, LLC | Huntsville, Alabama | Minimum |
Lessee, Lease, Description [Line Items] |
Lessee, Remaining term of contract | 42 years
LW Redstone Company, LLC | Huntsville, Alabama | Maximum |
Lessee, Lease, Description [Line Items] |
Lessee, Remaining term of contract | 51 years
M Square Associates, LLC | College Park, Maryland |
Lessee, Lease, Description [Line Items] |
Lessee, Right-of-use asset | $ 6.6
Lessee, Number of lease contracts | Lease | 4
M Square Associates, LLC | College Park, Maryland | Minimum |
Lessee, Lease, Description [Line Items] |
Lessee, Remaining term of contract | 62 years
M Square Associates, LLC | College Park, Maryland | Maximum |
Lessee, Lease, Description [Line Items] |
Lessee, Remaining term of contract | 73 years
Fort Meade/BW Corridor |
Lessee, Lease, Description [Line Items] |
Lessee, Right-of-use asset | $ 2.2
Lessee, Remaining term of contract | 47 years
Lessee, Number of lease contracts | Lease | 2

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