Funds Borrowed - Summary of Maturity of Broker Pools, Excluding Strategic Partner Reserve Deposits (Detail) $ in Thousands	Mar. 31, 2024 USD ($)
Debt Disclosure [Abstract]
Three months or less	$ 202,913
Over three months through six months	186,507
Over six months through one year	331,735
Over one year	1,160,691
Deposits	1,881,846
Strategic partner collateral deposits	1,500
Total deposits	$ 1,883,346

Collateral deposits.

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Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing after twelve months from the balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within six to twelve months after the balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three months or fewer from the balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three to six months after the balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit.

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