Revenue Recognition - Contract Balances with Customers (Details) $ in Millions	6 Months Ended
Jun. 30, 2026 USD ($)
Revenue from Contract with Customer [Abstract]
Trade receivables, beginning balance	$ 84.6
Trade receivables, ending balance	92.2
Increase (decrease) in trade receivables	(7.6)
Contract assets (current), beginning balance	0.0
Contract assets (current), ending balance	0.0
Increase (decrease) in contract assets (current)	0.0
Contract assets (non-current), beginning balance	2.9
Contract assets (non-current), ending balance	2.8
Increase (decrease) in contract assets (non-current)	(0.1)
Contract liabilities (current), beginning balance	1.3
Contract liabilities (current), ending balance	0.9
Increase (cecrease) in contract liabilities (current)	$ (0.4)

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

+ References

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

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Amount of increase (decrease) in current assets classified as other.

+ References

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Amount of increase (decrease) in current liabilities classified as other.

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Amount of increase (decrease) in noncurrent assets classified as other.

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- Definition

The increase (decrease) during the reporting period in the total amount due within one year (or one operating cycle) from all parties, associated with underlying transactions that are classified as operating activities.

+ References

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- Definition

Amount due from customers for fees and charges arising from transactions related to the entity's brokerage activities and operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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No definition available.

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