Assets held-for-sale - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disposal Group, Including Discontinued Operations [Line Items]
Noncash loss on assets held-for-sale	$ 10.7	$ 0.0	$ 10.7	$ 12.2
Disposal Group, Held-for-Sale, Not Discontinued Operations \| Office Property, Gaithersburg, Maryland
Disposal Group, Including Discontinued Operations [Line Items]
Disposal group, including discontinued operation, consideration	6.4		6.4
Noncash loss on assets held-for-sale	$ 10.7		$ 10.7

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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+ Details