The cash inflow associated with the sale of equity securities.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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No definition available.

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of loss from downward price adjustment on investment in equity security without readily determinable fair value.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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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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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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No definition available.

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Equity Securities (Narrative) (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 28, 2023	Dec. 31, 2022
Schedule Of Investments [Line Items]
Net (losses) gains on equity securities	$ 12.4	$ (65.0)
Net unrealized gains and (losses) on equity securities	11.7	(64.7)
Cash proceeds from sale of equity securities	11.1	83.2
Carrying amount of investment	8,452.1			$ 8,987.2
Offerpad Inc [Member]
Schedule Of Investments [Line Items]
Net unrealized gains and (losses) on equity securities	(44.0)
Payment for warrants to purchase additional shares of common stock	25.0
Warrants exercised to purchase shares of common stock			44.7
Carrying amount of investment	40.5			$ 14.8
Non Marketable Equity Securities
Schedule Of Investments [Line Items]
Impairment charges on equity securities	12.9
Net unrealized losses on equity securities	$ 17.2	11.1
Investment In Insurance Business
Schedule Of Investments [Line Items]
Realized gain on securities		51.1
Cash proceeds from sale of equity securities		$ 63.0