Leases - Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2025 USD ($) lease option office_space	Sep. 30, 2024 USD ($)
Leases [Abstract]
Number of ground leases classified as operating \| lease	3
Number of ground leases classified as financing \| lease	2
Total number of ground leases \| lease	5
Number of options to renew \| option	0
Number of office space \| office_space	2
Operating lease costs	$ 0.5	$ 0.5
Cash paid for operating lease liabilities	0.5	0.5
Continuing Operations
Lessor, Lease, Description [Line Items]
Operating lease income	70.6	74.1
Discontinued Operations \| Office Segment
Lessor, Lease, Description [Line Items]
Operating lease income	$ 72.6	$ 74.7

Finance Leases, Number of Ground Leases

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Leases, Number Of Ground Leases

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- Definition

Lessee, Operating Lease, Option To Renew

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Operating Leases, Number Of Ground Leases

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Operating Leases, Number of Office Space

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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