MERCHANDISE TRUSTS - Cost and Market Value Associated with Assets Held in Merchandise Trusts (Parenthetical) (Detail) - Merchandise Trusts - Variable Interest Entity, Primary Beneficiary $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) Extension	Dec. 31, 2020 USD ($) Extension
Schedule Of Available For Sale Securities [Line Items]
Number of potential lockup period extensions \| Extension	3	3
Lockup extension period	1 year	1 year
Unfunded investment commitments to private credit funds, callable at any time	$ 112.4	$ 47.8
Level 3
Schedule Of Available For Sale Securities [Line Items]
Direct loans, net of unamortized origination fees	$ 125.4
Minimum
Schedule Of Available For Sale Securities [Line Items]
Fixed income funds and equity funds, redemption period	1 day	1 day
Private credit funds, lockup periods	0 years	0 years
Maximum
Schedule Of Available For Sale Securities [Line Items]
Fixed income funds and equity funds, redemption period	30 days	30 days
Private credit funds, lockup periods	15 years	5 years

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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