Summary of Borrowed Funds (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Debt Outstanding [Line Items]
FHLB advances	$ 8,985,987	$ 10,183,132
Repurchase agreements	3,425,000	3,425,000
Fed funds purchased	495,000us-gaap_FederalFundsPurchased	260,000us-gaap_FederalFundsPurchased
Total wholesale borrowings	12,905,987nyb_TotalWholesaleBorrowings	13,868,132nyb_TotalWholesaleBorrowings
Junior subordinated debentures	358,415	358,355
Total borrowed funds	$ 13,264,402us-gaap_DebtAndCapitalLeaseObligations	$ 14,226,487us-gaap_DebtAndCapitalLeaseObligations

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

+ References

No definition available.

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- Definition

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.

+ References

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- Definition

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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- Definition

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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- 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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