Bank Deposits (Schedule of Deposits) (Details) (USD $)	Jun. 30, 2011	Dec. 31, 2010
Bank Deposits
Money market and savings accounts	$ 1,617,907,000	$ 1,590,663,000
Demand deposits (interest-bearing)	9,603,000	22,031,000
Demand deposits (non-interest-bearing)	11,017,000	8,197,000
Certificates of deposit	(2,552,000)	(2,677,000)
Bank deposits	1,641,079,000	1,623,568,000
Weighted average interest rate on deposits	0.20%	0.20%
Demand deposits (interest-bearing)	$ 1,600,000,000

A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.1)
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-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 8, 9
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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-Paragraph 1
-Article 5

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-Name Accounting Standards Codification
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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 12
-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Number AAG-DEP
-Chapter 13
-Paragraph 37, 38, 39
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
-Chapter V
-Section 563c.102
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Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

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-Publisher SEC
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Amount of deposits held by the entity for a related party (entity, shareholder, employee).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
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The weighted average interest rate for domestic time deposit liabilities.

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