Bank Deposits (Schedule Of Deposits) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Bank Deposits [Abstract]
Money market and savings accounts	$ 4,600,757us-gaap_DepositsMoneyMarketDeposits	$ 4,310,223us-gaap_DepositsMoneyMarketDeposits
Demand deposits (interest-bearing)	101,652	93,684
Certificates of deposit	77,197us-gaap_TimeDeposits	241,481us-gaap_TimeDeposits
Demand deposits (non-interest-bearing)	10,475	17,935
Bank deposits	$ 4,790,081us-gaap_Deposits	$ 4,663,323us-gaap_Deposits
Weighted average interest rate on deposits	0.19%	0.07%

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

+ Details

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- Definition

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

+ Details

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- Definition

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.

+ References

+ Details

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- Definition

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

+ References

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- Definition

Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ References

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- Definition

The weighted average interest rate for domestic time deposit liabilities.

+ References

No definition available.

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