Consolidated Statements of Financial Condition (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Securities held to maturity:
Fair value of mortgage-backed securities held to maturity	$ 4,810,218	$ 6,199,507
Fair value of investment securities held to maturity	$ 1,647,340	$ 3,867,488
Liabilities and Shareholders' Equity:
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	3,200,000,000	3,200,000,000
Common stock, shares issued	741,466,555	741,466,555
Common stock, shares outstanding	527,547,549	526,718,310
Treasury stock, shares	213,919,006	214,748,245

Securities held to maturity.

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- Definition

Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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Total number of shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Excludes common shares repurchased by the entity and held as Treasury shares. Shares outstanding equals shares issued minus shares held in treasury. Does not include common shares that have been repurchased.

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

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-Name Regulation S-X (SX)

-Number 210

-Section 04

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-Name Regulation S-X (SX)

-Number 210

-Section 02

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This item represents the total of all debt securities grouped by maturity dates, at fair value, which are categorized as held-to-maturity.

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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 securitized, pay-through debt securities collateralized by real estate mortgage loans (mortgages) as of the balance sheet date which have been categorized as held-to-maturity. The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity.

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-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 7

-Paragraph 15

-IssueDate 2006-05-01

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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