Borrowings - Schedule of Borrowings (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Debt Disclosure [Abstract]
Securities sold under agreements with customers to repurchase	$ 523,254	$ 412,743	$ 410,146
Federal funds purchased	25,350	17,350	1,725
Advances from Federal Home Loan Bank of Dallas	0		446,000
Total	$ 548,604	$ 430,093	$ 857,871

No definition available.

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- Definition

Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

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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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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