Assets held-for-sale - Schedule of assets held for sale (Details) - Disposal Group, Held-for-Sale, Not Discontinued Operations - Office Property, Gaithersburg, Maryland $ in Millions	Jun. 30, 2026 USD ($)
Disposal Group, Including Discontinued Operation, Assets [Abstract]
Property, plant and equipment, net	$ 16.8
Valuation allowance	(10.7)
Total assets held-for-sale	$ 6.1

Amount classified as assets attributable to disposal group held for sale or disposed of.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant