Assets Sold Under Agreements to Repurchase - Summary of Maturities of Outstanding Advances Under Repurchase Agreements by Maturity Date (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2026 USD ($)
Assets Sold under Agreements to Repurchase [Line Items]
Maturity of repurchase agreements	$ 8,383,792
Weighted average maturity (in months)	1 month 18 days
Within 30 days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Maturity of repurchase agreements	$ 5,873,114
Over 30 to 90 days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Maturity of repurchase agreements	2,029,097
Over 90 days to 180 days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Maturity of repurchase agreements	41,747
Over 180 Days to 1 Year [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Maturity of repurchase agreements	29,916
Over 1 year to 2 years [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Maturity of repurchase agreements	$ 409,918

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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+ Details