Subsequent events - Additional Information (Detail) - Subsequent event [Member] - Macquarie Management Holdings Inc [Member] ¥ in Billions, $ in Billions	Dec. 01, 2025 USD ($)	Dec. 01, 2025 JPY (¥)
Subsequent Event [Line Items]
Percentage of outstanding shares acquired in the acquired companies	100.00%	100.00%
Cash consideration for acquired outstanding shares	$ 1.8	¥ 281.4

Percentage of voting equity interest acquired in business combination.

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- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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