Funds Borrowed - Summary of Maturity of Deposit Pools and Savings Deposits, Including Strategic Partner Reserve Deposits (Detail) $ in Thousands	Mar. 31, 2026 USD ($)
Debt Disclosure [Abstract]
Three months or less	$ 241,634
Over three months through six months	159,896
Over six months through one year	298,919
Over one year	1,427,011
Deposits	2,127,460
Strategic partner collateral deposits	6,250
Total deposits	$ 2,133,710

Collateral deposits.

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- Definition

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.

+ References

No definition available.

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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.

+ References

No definition available.

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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.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

Amount of time deposit liabilities, including certificates of deposit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478353/942-405-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

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