Fair Value Measurements(Details 3) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Carrying Amount, Assets:
Cash and due from banks	$ 158,061	$ 175,769
Federal funds sold	3,102,168	493,628
Investment securities held to maturity	1,638,954	3,939,006
Investment securities available for sale	7,408	89,795
Federal Home Loan Bank of New York stock	726,564	871,940
Mortgage-backed securities held to maturity	4,533,557	5,914,372
Mortgage-backed securities available for sale	9,905,741	18,120,537
Loans	29,870,173	30,773,956
Estimated Fair Value, Assets:
Cash and due from banks	158,061	175,769
Federal funds sold	3,102,168	493,628
Investment securities held to maturity	1,647,340	3,867,488
Investment securities available for sale	7,408	89,795
Federal Home Loan Bank of New York stock	726,564	871,940
Mortgage-backed securities held to maturity	4,810,218	6,199,507
Mortgage-backed securities available for sale	9,905,741	18,120,537
Loans	30,789,138	32,328,933
Carrying Amount, Liabilities:
Deposits	25,421,419	25,173,126
Borrowed funds	20,225,000	29,675,000
Estimated Fair Value, Liabilities:
Deposits, Fair Value	25,579,030	25,584,478
Borrowed funds, Fair Value	$ 23,299,200	$ 32,975,633

Available for sale securities fair value.

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Borrowed funds.

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Borrowed funds fair value disclosure.

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Carrying amount, assets.

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Carrying amount, liabilities.

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Cash and due from banks fair value disclosure.

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Deposits fair value disclosure.

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Estimated fair value, assets.

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Estimated fair value, liabilities.

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Federal funds sold and other overnight deposits.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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