Summary of Borrowed Funds (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Debt Outstanding [Line Items]
FHLB advances	$ 10,529,244	$ 10,183,132
Repurchase agreements	3,325,000	3,425,000
Fed funds purchased	511,000	260,000
Total wholesale borrowings	14,365,244	13,868,132
Junior subordinated debentures	358,541	358,355
Total borrowed funds	$ 14,723,785	$ 14,226,487

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, 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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