Summary of Borrowed Funds (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Outstanding [Line Items]
FHLB advances	$ 13,053,661	$ 12,104,500
Repurchase agreements	500,000	450,000
Federal funds purchased
Total wholesale borrowings	13,553,661	12,554,500
Junior subordinated debentures	359,508	359,179
Subordinated notes	294,697
Total borrowed funds	$ 14,207,866	$ 12,913,679

Debt Outstanding [Line Items]

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As of the balance sheet date, the sum of FHLB advances, repurchase agreements and fed funds purchased.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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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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