Bank Deposits (Schedule of Deposits) (Details) (USD $)	Dec. 31, 2011	Dec. 31, 2010
Bank Deposits
Money market and savings accounts	$ 2,024,568,000.0	$ 1,590,663,000
Demand deposits (interest-bearing)	29,509,000.0	22,031,000
Demand deposits (non-interest-bearing)	15,691,000.0	8,197,000
Certificates of deposit	1,970,000.0	2,677,000
Bank deposits	2,071,738,000	1,623,568,000
Weighted average interest rate on deposits		0.20%
Demand deposits (interest-bearing)	$ 2,100,000,000	$ 1,600,000,000
Weighted Average Rate Domestic Deposit, Time Deposits		0.20%

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.

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-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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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.

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-Name Audit and Accounting Guide (AAG)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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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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Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

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

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The weighted average interest rate for domestic time deposit liabilities.

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