Borrowed Funds (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Securities sold under agreements to repurchase:
FHLB, Principal	$ 1,150,000	$ 2,150,000
FHLB, Weighted average rate	4.45%	4.29%
Other brokers, Principal	6,500,000	12,650,000
Other brokers, Weighted average rate	4.44%	4.00%
Total securities sold under agreements to repurchase, Principal	7,650,000	14,800,000
Total securities sold under agreements to repurchase, Weighted average rate	4.44%	4.04%
Advances from the FHLB, Principal	12,575,000	14,875,000
Advances from the FHLB, Weighted average rate	3.46%	3.99%
Total borrowed funds, Principal	20,225,000	29,675,000
Total borrowed funds, Weighted average rate	3.83%	4.02%
Accrued interest payable, Principal	$ 109,188	$ 151,215

Borrowed funds.

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- Definition

Securities sold under agreements to repurchase to federal home loan bank.

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- Definition

Securities sold under agreements to repurchase to other brokers.

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- Definition

Weighted average rate borrowed funds.

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- Definition

Weighted average rate securities sold under agreements to repurchase.

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- Definition

Weighted average rate Securities sold under agreements to repurchase federal home loan bank.

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- Definition

Weighted average rate securities sold under agreements to repurchase other brokers.

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- Definition

The dollar amount of advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 15

-Paragraph 17, 37

-IssueDate 2006-05-01

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 10

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- Definition

Describes the weighted average interest rate applicable to the specific advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 15

-Paragraph 17, 37

-IssueDate 2006-05-01

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- Definition

Gross expenses on securities sold coupled with an agreement to repurchase the same from the same counterparty at a fixed or determinable price within a fixed or variable time period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 7

-Subsection II

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- Definition

The carrying value as of the balance sheet date of securities that an institution sells and agrees to repurchase (the identical or substantially the same securities) as a seller-borrower at a specified date for a specified price, also known as a repurchase agreement, or repo. Most repos involve obligations of the federal government or its agencies, but other financial instruments, such as commercial paper, banker's acceptances, and negotiable certificates of deposit, are sometimes used in repos.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph 1

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 100

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-BRD

-Chapter 4

-Paragraph 36

-IssueDate 2006-05-01

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