Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Related Person Transactions (Details) - Two North Riverside Plaza Joint Venture Limited Partnership - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Apr. 30, 2024	Dec. 31, 2023	Aug. 31, 2023
Related Party Transaction [Line Items]
Lease payment				$ 0.4	$ 0.4
Operating lease, expense	$ 0.1	$ 0.1
Subsequent event
Related Party Transaction [Line Items]
Lease payment			$ 0.4